Chapter 2. Atoms and Elements

Size: px
Start display at page:

Download "Chapter 2. Atoms and Elements"

Transcription

1 Chapter 2. Atoms and Elements John Dalton Robert Millikan J.J. Thomson Ernest Rutherford The Components of Matter Elements, Compounds, Mixtures Dalton s Atomic Theory Modern Atomic Theory Atomic and Mass Number Formulas, and Masses Modified by Dr. Cheng-Yu Lai 1

2 Modern Atomic Theory and the Laws That Led to It The three most important laws that led to the development and acceptance of the atomic theory are as follows: The law of conservation of mass The law of definite proportions The law of multiple proportions 2014 Pearson Education, Inc.

3 Conservation of Mass Law of Conservation of Mass: Mass is neither created nor destroyed in chemical reactions. Aqueous solutions of mercury(ii) nitrate and potassium iodide will react to form a precipitate of mercury(ii) iodide and aqueous potassium iodide g g = 6.57 g Hg(NO3)2(aq) + 2KI(aq) HgI2(s) + 2KNO3(aq) 4.55 g g = 6.57 g 2012 Pearson Education, Inc. Chapter 2/3

4 Conservation of Mass If the product weight is more than reactant weight, what does this indicate? Error from left over in your lab rinse your beaker 2012 Pearson Education, Inc. Chapter 2/4

5 The Law of Definite Proportions Law of Definite Proportions: Different samples of a pure chemical substance always contain the same proportion of elements by mass. For example, the decomposition of 18.0 g of water results in 16.0 g of oxygen and 2.0 g of hydrogen, or an oxygen-to-hydrogen mass ratio of: By mass, H2O water is: 88.8 % oxygen, 11.2 % hydrogen 2012 Pearson Education, Inc. Chapter 2/5

6 Example 2.1 Law of Definite Proportions Two samples of carbon dioxide are decomposed into their constituent elements. One sample produces 25.6 g of oxygen and 9.60 g of carbon, and the other produces 21.6 g of oxygen and 8.10 g of carbon. Show that these results are consistent with the law of definite proportions. Solution To show this, calculate the mass ratio of one element to the other for both samples by dividing the mass of one element by the mass of the other. For convenience, divide the larger mass by the smaller one. For the first sample: For the second sample: The ratios are the same for the two samples, so these results are consistent with the law of definite proportions. No matter where is CO2 from, the mass ratio between Oxygen and Carbon is the same Chemistry: A Molecular Approach, 3rd Edition Nivaldo J. Tro 2014 Pearson Education, Inc.

7 The Law of Multiple Proportions In 1804, John Dalton published his law of multiple proportions. When two elements (call them A and B) form two different compounds, the masses of element B that combine with element A can be expressed as a ratio of small whole numbers. An atom of A combines with either one, two, three, or more atoms of B (AB1, AB2, AB3, etc.) Pearson Education, Inc. Chapter 2/7

8 [2Oxygen] CO 2 [1Carbon] [1Oxygen] CO [1Carbon] CO 2 [2Oxygen / 1Carbon] 2 CO [1Oxygen / 1Carbon] 2014 Pearson Education, Inc.

9 Dalton s Atomic Theory (1808) John Dalton All matter is composed of extremely small particles called atoms Atoms of a given element are identical in size, mass, and other properties; atoms of different elements differ in size, mass, and other properties Atoms cannot be subdivided, created, or destroyed Atoms of different elements combine in simple whole-number ratios to form chemical compounds In chemical reactions, atoms are combined, separated, or rearranged Please memorize these 2012 Pearson Education, Inc. 9

10 Cathode Ray Experiment - Discovery of the Electron In 1897, J.J. Thomson used a cathode ray tube to deduce the presence of a negatively charged particle. Cathode ray tubes pass electricity through a gas that is contained at a very low pressure. J. J. Thomson measured the charge-to-mass ratio ( e/m) of the cathode ray particles by deflecting them using electric and magnetic fields, as shown in the figure. The value he measured was coulombs (C) per gram Pearson Education, Inc. 10

11 Millikan s Oil Drop Experiment: The Charge of the Electron American physicist Robert Millikan ( ), performed his now famous oil drop experiment in which he deduced the charge of a single electron. The measured charge on any drop was always a whole-number multiple of , the fundamental charge of a single electron Pearson Education, Inc.

12 Mass of the Electron With this number in hand, and knowing Thomson s mass-to-charge ratio for electrons, we can deduce the mass of an electron: g C X 1/ ( coulombs (C) / g) 1909 Robert Millikan determines the mass of the electron. The drop 2014oil Pearson Education, apparatus Inc. Mass of the electron is x kg

13 Conclusions from the Study of the Electron Cathode rays have identical properties regardless of the element used to produce them. All elements must contain identically charged electrons. Atoms are neutral, so there must be positive particles in the atom to balance the negative charge of the electrons Electrons have so little mass that atoms must contain other particles that account for most of the mass 2012 Pearson Education, Inc. plum-pudding model.13

14 Thomson s Atomic Model J.J. Thomson Thomson believed that the electrons were like plums embedded in a positively charged pudding, thus it was called the plum pudding model Pearson Education, Inc. 14

15 Rutherford s Gold Foil Experiment In 1909, Ernest Rutherford ( ), who had worked under Thomson and subscribed to his plum-pudding model, performed an experiment in an attempt to confirm Thomson s model. In the experiment, Rutherford directed the positively charged particles at an ultra thin sheet of gold foil Pearson Education, Inc. Chapter 2/15

16 Rutherford s Gold Foil Experiment Alpha particles are helium nuclei Particles were fired at a thin sheet of gold foil Particle hits on the detecting screen (film) are recorded 2012 Pearson Education, Inc. 16

17 Rutherford s Gold Foil Experiment He concluded that matter must not be as uniform as it appears. It must contain large regions of empty space dotted with small regions of very dense matter Pearson Education, Inc. Chapter 2/17

18 Rutherford s Findings Most of the particles passed right through A few particles were deflected VERY FEW were greatly deflected Rutherford proposed that the atom must consist mainly of empty space with the mass concentrated in a tiny central core the nucleus. Conclusions: The nucleus is small The nucleus is dense The nucleus is positively charged 18

19 Rutherford s nuclear theory Building on this idea, he proposed the nuclear theory of the atom, with three basic parts: 1. Most of the atom s mass and all of its positive charge are contained in a small core called a nucleus. 2. Most of the volume of the atom is empty space, throughout which tiny, negatively charged electrons are dispersed. 3. There are as many negatively charged electrons outside the nucleus as there are positively charged particles (named protons) within the nucleus (named neutrons), so that the atom is electrically neutral. Later work by Rutherford and one of his students, British scientist James Chadwick ( ), demonstrated that the previously unaccounted for mass was due to Chapter neutrons, neutral particles within the nucleus Pearson Education, Inc. 2/19

20 Atomic Particles are composed of the same subatomic particles: Particle Electron Proton Neutron Charge Mass (kg) x x Location Electron cloud Nucleus x Nucleus The charge of the proton is opposite in sign but equal to that of the electron. The mass of the atom is primarily in the nucleus. The mass of a neutron is similar to that of a proton Pearson Education, Inc. 20

21 Atomic Numbers The sum of the number of neutrons and protons in an atom is its mass number and is represented by the symbol A A = number of protons (p) + number of neutrons (n) where X is the chemical symbol, A is the mass number, and Z is the atomic number Pearson Education, Inc. Chapter 2/21

22 Atomic Number in Periodic Table 2014 Pearson Education, Inc.

23 Atomic Number Atomic number (Z) of an element is the number of protons in the nucleus of each atom of that element. Element Carbon Phosphorus Gold # of protons Atomic # (Z) Pearson Education, Inc

24 Mass Number Mass number is the number of protons and neutrons in the nucleus of an isotope. Mass # = p+ + n0 Nuclide p+ n0 e- Mass # Oxygen Arsenic - 75 Phosphorus How many protons, electrons, and neutrons are present in an atom of? Nuclide Cr p 2012 Pearson Education, Inc. 24 n 28 e 24 Mass # 52 24

25 Isotopes: Varied Number of Neutrons carbon-12 mass number 12 6C 6 protons 6 electrons 6 neutrons 14 6C 6 protons 6 electrons 8 neutrons atomic number carbon-14 mass number atomic number Atoms with the same number of protons but a different 2012 Pearson Education, Inc. 25 number of neutrons are called isotopes.

26 Atomic Masses The mass of 1 atom of carbon-12 is defined to be 12 amu. Atomic mass is the average of all the naturally isotopes of that element Pearson Education, Inc. Chapter 2/26

27 Atomic Masses Isotope Symbol Composition of the nucleus % in nature amu Carbon12 12C 6 protons 6 neutrons 98.89% Carbon13 13C 6 protons 7 neutrons 1.11% Carbon14 14C 6 protons 8 neutrons <0.01% mass of carbon = (12 amu)(0.9889) + ( amu)(0.0111) + ( amu)(0.0001) = amu amu amu 2012 Pearson Education, Inc. = amu 2012 Pearson Education, Inc. 1 Carbon Atomic Mass = amu 27

28 Example 2.5 Atomic Mass Copper has two naturally occurring isotopes: Cu-63 with a mass of amu and a natural abundance of 69.17%, and Cu-65 with a mass of amu and a natural abundance of 30.83%. Calculate the atomic mass of copper. Solution Convert the percent natural abundances into decimal form by dividing by 100. Calculate the atomic mass using the equation given in the text. Chemistry: A Molecular Approach, 3rd Edition Nivaldo J. Tro 2014 Pearson Education, Inc.

29 Modern Atomic Theory # 1 Several changes have been made to Dalton s theory. Dalton said: Atoms of a given element are identical in size, mass, and other properties; atoms of different elements differ in size, mass, and other properties Modern theory states: Atoms of an element have a characteristic average mass which is unique to that element Pearson Education, Inc. Chapter 2/29

30 Modern Atomic Theory #2 Dalton said: Atoms cannot be subdivided, created, or destroyed Modern theory states: Atoms cannot be subdivided, created, or destroyed in ordinary chemical reactions. However, these changes CAN occur in nuclear reactions 2012 Pearson Education, Inc. Chapter 2/30

31 Moles and Formula Mass 2012 Pearson Education, Inc. 31

32 Converting between Number of Moles and Number of Atoms 1 dozen = 12 1 mole = x 1023 For example, 1 mol of marbles corresponds to marbles. 1 mol of sand grains corresponds to sand grains. One mole of anything is units of that thing. 1 mole C = x 1023 C atoms The conversion factors take the following forms: 2012 Pearson Education, Inc. 32

33 Atomic Masses and the Mole Avogadro s Number (NA): One mole of any substance contains x 1023 formula units. Molar Mass: The mass in grams of one mole of any element. It is numerically equivalent to its atomic mass. Amadeo Avogadro x 1023 is called Avogadro s Number in honor 2012Amadeo Pearson Education, Inc. Chapter 2/33 of the Italian chemist Avogadro ( ).

34 Converting between Mass and Amount (Number of Moles) The mass of 1 mol of atoms of an element is the ATOMIC molar mass. For example, H=1, C=12.01 found in the periodic table An element s molar mass in grams per mole is numerically equal to the element s atomic mass in atomic mass units (amu = g/mole). 1 mole H= 1 g 1 mole C = g 2014 Pearson Education, Inc.

35 Conceptual Plan We now have all the tools to count the number of atoms in a sample of an element by weighing it. First, we obtain the mass of the sample. Then, we convert it to the amount in moles using the element s molar mass. Finally, we convert it to the number of atoms using Avogadro s number. The conceptual plan for these kinds of calculations takes the following form: 2014 Pearson Education, Inc.

36 Calculations with Moles: Converting moles to grams How many grams of lithium are in 3.50 moles of lithium? 3.50 mol Li 6.94 g Li 1 mol Li = 2012 Pearson Education, Inc g Li 36

37 Calculations with Moles: Converting grams to moles How many moles of lithium are in 18.2 grams of lithium? 18.2 g Li 1 mol Li 6.94 g Li = 2.62 mol Li 2012 Pearson Education, Inc. 37

38 Calculations with Moles: Using Avogadro s Number How many atoms of lithium are in 3.50 moles of lithium? 3.50 mol 6.02 x 1023 atoms 1 mol 2012 Pearson Education, Inc. = 2.07 x 1024 atoms 38

39 Calculations with Moles: Using Avogadro s Number How many atoms of lithium are in 18.2 g of lithium? 18.2 g Li 1 mol Li 6.94 g Li x 1023 atoms Li 1 mol Li (18.2)(6.022 x 1023)/6.94 = 1.58 x 1024 atoms Li 2012 Pearson Education, Inc. 39

40 Compound Formula Mass A compound is a pure substance made of two or more elements chemically joined together. The mass of an individual molecule or formula unit also known as molecular mass or molecular weight Mass of 1 molecule of H2O = 2(1.01 amu H) amu O = amu 1. Know chemical formula 2. Count the atoms from chemical formula 3. Sum of the masses of the atoms in a single molecule or formula unit whole = sum of the parts!

41 Identifying Elements and Formula Subscripts Each new element is identified by a capital letter H2O There are 2 atoms of Hydrogen There are 1 atoms of Oxygen If there is not a subscript listed, it is understood to be 1. Example: NaCl There is one atom of Sodium There is one atom of Chlorine Example: H2SO4 The elements in Sulfuric Acid Hydrogen 2H Sulfur 1S Oxygen 4O

42 Molar Mass of Compounds The molar mass of a compound the mass in grams of 1 mol of its molecules or formula units is equivalent to its formula mass. 1 mole of H2O contains 2 moles of H and 1 mole of O: molar mass = 1 mole H2O = 2(1.01 g H) g O = g so the molar mass of H2O is g/mole Molar mass = formula mass (in g/mole)

43 Calculating Formula Mass Its the sum of the individual atomic masses of each atom constituting the molecular elements and compound. 1. Count atoms from chemical formula 2 Nitrogen 1 gold HCl NaHCO3 Hydrogen 1 Chlorine - 1 Sodium 1 Hydrogen 1 Carbon 1 Oxygen Sum of the individual atomic masses 2(14.01 g) = 2 Nitrogen 1(14.01 g) = 1 gold

44 Calculating Formula Mass Its the sum of the individual atomic masses of each atom constituting the molecule. Calculate the formula mass of 1 mole of magnesium carbonate, MgCO g g + 3(16.00 g) = g/mole Molar Mass: The mass in grams of one mole of any element. It is numerically equivalent to its atomic mass.

45 Calculating Percentage Composition Calculate the percentage composition of magnesium carbonate, MgCO3. From previous slide: g g + 3(16.00 g) = g Mg % C % O %

46 Periodic Table The periodic table can also be divided into main-group elements, whose properties tend to be largely predictable based on their position in the periodic table. transition elements or transition metals, whose properties tend to be less predictable based simply on their position in the periodic table Pearson Education, Inc.

47 Ions: Losing and Gaining Electrons The number of electrons in a neutral atom is equal to the number of protons in its nucleus (designated by its atomic number Z). Positively charged ions, such as Na+, are called cations. Negatively charged ions, such as F, are called anions Pearson Education, Inc.

48 Ions and the Periodic Table In a chemical changes, however, atoms can lose or gain electrons and become charged particles called ions. A main-group metal tends to lose electrons, forming a cation with the same number of electrons as the nearest noble gas. A main-group nonmetal tends to gain electrons, forming an anion with the same number of electrons as the nearest noble gas Pearson Education, Inc.

49 Ions and the Periodic Table 2014 Pearson Education, Inc.

50 Predicting Ionic Charges Group 1: Lose 1 electron to form 1+ ions H+ Li+ Na+ K+ Rb+ 33) Give the number of protons in Na+1. A) 10 B) 13 C) 9 D) 11 E) 12 Answer: D number of electrons becomes 10 Cs+

51 Predicting Ionic Charges Group 2: Loses 2 electrons to form 2+ ions Be2+ Mg2+ Ca2+ Sr2+ Ba2+ 30) What is the identity of element Q if the ion Q2+ contains 10 electrons? A) C B) O C) Ne D) Mg Answer: D

52 Predicting Ionic Charges B3+ Al3+ Ga3+ Group 13: Loses 3 electrons to form 3+ ions

53 Predicting Ionic Charges C22- C4- Caution! and are both called carbide Group 14: Loses 4 electrons or gains 4 electrons

54 Predicting Ionic Charges N3- Nitride P3- Phosphide As3- Arsenide Group 15: Gains 3 electrons to form 3- ions 32) Give the number of electrons in P-3. A) 18 B) 12 C) 19 D) 15 E) 16 Answer A and the number of protons is 15

55 Predicting Ionic Charges O2- Oxide S2- Sulfide Se2- Selenide Group 16: Gains 2 electrons to form 2- ions

56 Predicting Ionic Charges F1- Fluoride Cl1- Chloride Br1- Bromide I1- Iodide Group 17: Gains 1 electron to form 1- ions

57 Ions and the Periodic Table In general, the alkali metals (group 1A) have a tendency to lose one electron and form 1+ ions. The alkaline earth metals (group 2A) tend to lose two electrons and form 2+ ions. The halogens (group 7A) tend to gain one electron and form 1 ions. The oxygen family nonmetals (group 6A) tend to gain two electrons and form 2 ions Pearson Education, Inc.

58 Ions and the Periodic Table For the main-group elements that form cations with predictable charge, the charge is equal to the group number. For main-group elements that form anions with predictable charge, the charge is equal to the group number minus eight. Transition elements may form various different ions with different charges Pearson Education, Inc.

59 Example 2.6 Converting between Number of Moles and Number of Atoms Calculate the number of copper atoms in 2.45 mol of copper. Sort You are given the amount of copper in moles and asked to find the number of copper atoms. Given: 2.45 mol Cu Find: Cu atoms Strategize Convert between number of moles and number of atoms by using Avogadro s number as a conversion factor. Conceptual Plan Relationships Used = 1 mol (Avogadro s number) Chemistry: A Molecular Approach, 3rd Edition Nivaldo J. Tro 2014 Pearson Education, Inc.

60 Example 2.8 The Mole Concept Converting between Mass and Number of Atoms How many copper atoms are in a copper penny with a mass of 3.10 g? (Assume that the penny is composed of pure copper.) Sort You are given the mass of copper and asked to find the number of copper atoms. Given: 3.10 g Cu Find: Cu atoms Strategize Convert between the mass of an element in grams and the number of atoms of the element by first converting to moles (using the molar mass of the element) and then to number of atoms (using Avogadro s number). Conceptual Plan Relationships Used g Cu = 1 mol Cu (molar mass of copper) = 1 mol (Avogadro s number) Chemistry: A Molecular Approach, 3rd Edition Nivaldo J. Tro 2014 Pearson Education, Inc.

Atoms, Molecules, Formulas, and Subatomic Particles

Atoms, Molecules, Formulas, and Subatomic Particles Introduction to Chemistry Chapter 5 1 Atoms, Molecules, Formulas, and Subatomic Particles The Atom: The smallest particle of an element that can exist and still have the properties of the element building

More information

2014 Spring CHEM101 Ch1-2 Review Worksheet Modified by Dr. Cheng-Yu Lai,

2014 Spring CHEM101 Ch1-2 Review Worksheet Modified by Dr. Cheng-Yu Lai, Ch1 1) Which of the following underlined items is not an intensive property? A) A chemical reaction requires 3.00 g of oxygen. B) The density of helium at 25 C is 1.64 10-4 g/cm3. C) The melting point

More information

Chapter Two Study Guide Answers

Chapter Two Study Guide Answers Chapter Two Study Guide Answers Concepts 1. Know the law of conservation of mass 2. Know about the structure of the atom and who did what including Thomson, Rutheford, Millikan, Bohr 3. Know the three

More information

Chapter 2 Atoms, Ions, and the Periodic Table

Chapter 2 Atoms, Ions, and the Periodic Table Chapter 2 Atoms, Ions, and the Periodic Table 2.1 (a) neutron; (b) law of conservation of mass; (c) proton; (d) main-group element; (e) relative atomic mass; (f) mass number; (g) isotope; (h) cation; (i)

More information

Theories of Matter Composition

Theories of Matter Composition Chapter 2 Theories of Matter Composition Democritus (5 th 4 th century BC) ATOMISM Aristotle (4 th 5 th century BC) CONTINUOUS MATTER FOUR ELEMENTS Earth, Air, Fire, Water Boyle (17 th century) Reintroduced

More information

ATOMS A T O M S, I S O T O P E S, A N D I O N S. The Academic Support Center @ Daytona State College (Science 120, Page 1 of 39)

ATOMS A T O M S, I S O T O P E S, A N D I O N S. The Academic Support Center @ Daytona State College (Science 120, Page 1 of 39) ATOMS A T O M S, I S O T O P E S, A N D I O N S The Academic Support Center @ Daytona State College (Science 120, Page 1 of 39) THE ATOM All elements listed on the periodic table are made up of atoms.

More information

1) Scientific law = a generalization of scientific observations that describes what happens (does not explain)

1) Scientific law = a generalization of scientific observations that describes what happens (does not explain) I. Law vs. Theory 1) Scientific law = a generalization of scientific observations that describes what happens (does not explain) 2) Theory (model) = a set of assumptions used to explain observations and

More information

9/13/2013. However, Dalton thought that an atom was just a tiny sphere with no internal parts. This is sometimes referred to as the cannonball model.

9/13/2013. However, Dalton thought that an atom was just a tiny sphere with no internal parts. This is sometimes referred to as the cannonball model. John Dalton was an English scientist who lived in the early 1800s. Dalton s atomic theory served as a model for how matter worked. The principles of Dalton s atomic theory are: 1. Elements are made of

More information

5 Early Atomic Theory and Structure. Chapter Outline. Dalton s Model of the Atom. Dalton s Model of the Atom. Dalton s Model of the Atom 10/2/2013

5 Early Atomic Theory and Structure. Chapter Outline. Dalton s Model of the Atom. Dalton s Model of the Atom. Dalton s Model of the Atom 10/2/2013 5 Early Atomic Theory and Structure Chapter Outline 5.1 5.2 Electric Charge A. Discovery of Ions 5.3 Subatomic Parts of the Atom Lightning occurs when electrons move to neutralize charge difference between

More information

Elements, Atoms & Ions

Elements, Atoms & Ions Introductory Chemistry: A Foundation FOURTH EDITION by Steven S. Zumdahl University of Illinois Elements, Atoms & Ions Chapter 4 1 2 Elements Aims: To learn about the relative abundances of the elements,

More information

1/7/2013. Chapter 2. Atoms and the Periodic Table. Chemistry: Atoms First Julia Burdge & Jason Overby. 2.1 Atoms First

1/7/2013. Chapter 2. Atoms and the Periodic Table. Chemistry: Atoms First Julia Burdge & Jason Overby. 2.1 Atoms First Chemistry: Atoms First Julia Burdge & Jason Overby 2 Atoms and the Periodic Table Chapter 2 Atoms and the Periodic Table Kent L. McCorkle Cosumnes River College Sacramento, CA Copyright (c) The McGraw-Hill

More information

CHEMISTRY Matter and Change

CHEMISTRY Matter and Change CHEMISTRY Matter and Change Chapter 4: The Structure of the Atom CHAPTER 4 Section 4.1 Section 4.2 Section 4.3 Section 4.4 Table Of Contents Early Ideas About Matter Defining the Atom How Atoms Differ

More information

Atoms, Ions and Molecules The Building Blocks of Matter

Atoms, Ions and Molecules The Building Blocks of Matter Atoms, Ions and Molecules The Building Blocks of Matter Chapter 2 1 Chapter Outline 2.1 The Rutherford Model of Atomic Structure 2.2 Nuclides and Their Symbols 2.3 Navigating the Periodic Table 2.4 The

More information

Chapter 4: Atoms and Elements

Chapter 4: Atoms and Elements C h e m i s t r y 1 2 C h 4 : A t o m s a n d E l e m e n t s P a g e 1 Chapter 4: Atoms and Elements Bonus Problems: 27, 29, 33, 35, 45, 51, 53, 67, 69, 73, 83, 87, 93, 95, 107, 109 Early Ideas on Matter:

More information

Subatomic Particle Data and a Periodic Table of the Elements can be found at the End of the Exam.

Subatomic Particle Data and a Periodic Table of the Elements can be found at the End of the Exam. CHEM 109 Introduction to Chemistry Fall 2016 Name: Examination 3 Multiple Choice Questions Subatomic Particle Data and a Periodic Table of the Elements can be found at the End of the Exam. 1. Elemental

More information

Chapter 3 Atoms and Moles. Section 1 Substances Are Made of Atoms

Chapter 3 Atoms and Moles. Section 1 Substances Are Made of Atoms + Chapter 3 Atoms and Moles Section 1 Substances Are Made of Atoms + Atomic Theory Atomic Theory explains three separate scientific laws Model on the right is more accurate depiction of an atom + Law of

More information

Name Date Period. Chemistry: Unit 3 - Atoms Test Review KEY

Name Date Period. Chemistry: Unit 3 - Atoms Test Review KEY Name Date Period Concepts to know for the Unit 3 test: Chemistry: Unit 3 - Atoms Test Review KEY 1. Summarize the major experimental evidence that led to the development of various atomic models, both

More information

b. How is the modern periodic table arranged? In order of increasing atomic number

b. How is the modern periodic table arranged? In order of increasing atomic number Unit 3 Review Chapters 4 (Atomic Structure) & 6 (Periodic Table) Part 1: Answer the following questions. 1. a. Which scientist created the first modern atomic theory? John Dalton b. What was his theory?

More information

Unit 6 Particles with Internal Structure 3-1

Unit 6 Particles with Internal Structure 3-1 Unit 6 Particles with Internal Structure 3-1 The Elements Remember, elements are combined to form molecules the way letters are combined to form words. Presently there are about 115 known elements. Only

More information

ATOMIC STRUCTURE AND THE PERIODIC TABLE

ATOMIC STRUCTURE AND THE PERIODIC TABLE 5 ATOMIC STRUCTURE AND THE PERIODIC TABLE Conceptual Curriculum Concrete concepts More abstract concepts or math/problem-solving Standard Curriculum Core content Extension topics Honors Curriculum Core

More information

Early Atomic Theory and Structure. Beginning Days (Theory of an Atom) Beginning Days 8/14/2011. Chapter 5

Early Atomic Theory and Structure. Beginning Days (Theory of an Atom) Beginning Days 8/14/2011. Chapter 5 Early Atomic Theory and Structure Chapter 5 Beginning Days (Theory of an Atom) 5 th century B.C., Greek philosophers Empedocles and Democritus proposed their own theories about an atom. Empedocles stated

More information

Chapter 2: Atoms, Molecules and Ions. Dalton s Atomic Theory ( ) Postulates

Chapter 2: Atoms, Molecules and Ions. Dalton s Atomic Theory ( ) Postulates Chapter 2: Atoms, Molecules and Ions The topics in this chapter should be review from a previous course. It is expected that you are able to review and master this material quickly and somewhat independently.

More information

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. CHM115 Exam #1 A Name: MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The number with the most significant zeros is. A) 2.501 10-7 B) 0.00002510

More information

2 The Structure of Atoms

2 The Structure of Atoms CHAPTER 4 2 The Structure of Atoms SECTION Atoms KEY IDEAS As you read this section, keep these questions in mind: What do atoms of the same element have in common? What are isotopes? How is an element

More information

Chapter 2 Atoms, Molecules, and Ions

Chapter 2 Atoms, Molecules, and Ions Chapter 2 Atoms, Molecules, and Ions 1 Self study: The history of the development of atomic theory. 9 th Ed: pp. 36-41 or 10 th Ed: pp. 38-42. 2 The Atomic Theory of Matter John Dalton (1766-1844), began

More information

CHAPTER 4: ATOMIC STRUCTURE. Intro Video! (nothing about Bohr, I promise)

CHAPTER 4: ATOMIC STRUCTURE. Intro Video! (nothing about Bohr, I promise) CHAPTER 4: ATOMIC STRUCTURE Intro Video! (nothing about Bohr, I promise) I. HISTORY OF ATOMIC THEORY A. Highlights: 1. Democritus: suggested matter was made of tiny indivisible particles 2. Aristotle:

More information

Chapter 4 Atoms and Elements

Chapter 4 Atoms and Elements Chemistry 25 Chapter 4 Atoms and Elements Experiencing Atoms What is ATOM? Atoms are incredibly small, yet they compose everything. Atoms are the pieces of elements. Properties of the atoms determine the

More information

6) Which one of the following is a nonmetal? A) Zn B) Au C)Pb D) Ca E) I Answer: E

6) Which one of the following is a nonmetal? A) Zn B) Au C)Pb D) Ca E) I Answer: E CHM115 Exam #1 B Name: MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Of the following, only is a chemical reaction. A) tarnishing of silver B)

More information

PERIODIC TABLE OF GROUPS OF ELEMENTS Elements can be classified using two different schemes.

PERIODIC TABLE OF GROUPS OF ELEMENTS Elements can be classified using two different schemes. 1 PERIODIC TABLE OF GROUPS OF ELEMENTS Elements can be classified using two different schemes. Metal Nonmetal Scheme (based on physical properties) Metals - most elements are metals - elements on left

More information

Name Date Class ATOMIC STRUCTURE

Name Date Class ATOMIC STRUCTURE Name Date Class 4 ATOMIC STRUCTURE SECTION 4.1 DEFINING THE ATOM (pages 101 103) This section describes early atomic theories of matter and provides ways to understand the tiny size of individual atoms.

More information

Chapter 2: Atoms and Elements

Chapter 2: Atoms and Elements C h e m i s t r y 1 A C h a p t e r 2 P a g e 1 Chapter 2: Atoms and Elements Homework: Read Chapter 2: Work out sample/practice exercises. Bonus Chapter 2 Problems: 31, 37, 39, 41, 47, 53, 59, 61, 67,

More information

Atomic Calculations. 2.1 Composition of the Atom. number of protons + number of neutrons = mass number

Atomic Calculations. 2.1 Composition of the Atom. number of protons + number of neutrons = mass number 2.1 Composition of the Atom Atomic Calculations number of protons + number of neutrons = mass number number of neutrons = mass number - number of protons number of protons = number of electrons IF positive

More information

Atoms, Elements, and the Periodic Table (Chapter 2)

Atoms, Elements, and the Periodic Table (Chapter 2) Atoms, Elements, and the Periodic Table (Chapter 2) Atomic Structure 1. Historical View - Dalton's Atomic Theory Based on empirical observations, formulated as Laws of: Conservation of Mass Definite Proportions

More information

Chemistry 101 Chapter 2 ATOMIC MODEL. atoms (Carbon atoms in diamond) molecules (H 2 O molecules in water) ions (Na + and Cl ions in sodium chloride)

Chemistry 101 Chapter 2 ATOMIC MODEL. atoms (Carbon atoms in diamond) molecules (H 2 O molecules in water) ions (Na + and Cl ions in sodium chloride) ATOMIC MODEL All forms of matter are made up of PARTICLES These PARTICLES may be: atoms (Carbon atoms in diamond) molecules (H 2 O molecules in water) ions (Na + and Cl ions in sodium chloride) The particulate

More information

Lecture 4 - Observations that Led to the Nuclear Model of the Atom. Chem 103, Section F0F Unit I - An Overview of Chemistry Lecture 4

Lecture 4 - Observations that Led to the Nuclear Model of the Atom. Chem 103, Section F0F Unit I - An Overview of Chemistry Lecture 4 Chem 103, Section F0F Unit I - An Overview of Chemistry Lecture 4 Some observations that led to the nuclear model for the structure of the atom The modern view of the atomic structure and the elements

More information

2. All of the atoms of argon have the same. 1. The atomic number of an atom is always equal to the total number of. A. mass number B.

2. All of the atoms of argon have the same. 1. The atomic number of an atom is always equal to the total number of. A. mass number B. 1. The atomic number of an atom is always equal to the total number of A. neutrons in the nucleus B. protons in the nucleus 2. All of the atoms of argon have the same A. mass number B. atomic number C.

More information

Atom nucleus (protons and neutrons) electron cloud (electrons)

Atom nucleus (protons and neutrons) electron cloud (electrons) Atom nucleus (protons and neutrons) electron cloud (electrons) Atomic Number equal to the number of protons Mass Number protons + neutrons Charge when # of electrons # of protons Negatively Charged Ion

More information

Chapter 2. Atomic Theory

Chapter 2. Atomic Theory Chapter 2 Atomic Theory 400 B.C.E. atomists 1804 C.E. Dalton 1903 Thompson A History of Atomic Models 1932 Chadwick 1913 Bohr 1911 Rutherford Early Philosophy of Matter Some early philosophers believed

More information

Atomic Structure Practice Test

Atomic Structure Practice Test Atomic Structure Practice Test Multiple Choice Identify the choice that best completes the statement or answers the question. 1. If 6.0 g of element K combine with 17 g of element L, how many grams of

More information

CHM-101-A Exam 1 Version 1 September 12, 2006

CHM-101-A Exam 1 Version 1 September 12, 2006 CHM-101-A Exam 1 Version 1 1. Which of the following does not apply to a chemical compound? A. A chemical compound consists of two or more elements. B. The elements in a compound are combined in definite

More information

location in the atom relative mass relative charge

location in the atom relative mass relative charge WAHS Chemistry Unit 4: Atomic Structure 1 Unit Assignment #1 Complete the Important Chemistry Scientists assignment that will be assigned. Be sure to know all of the scientists and their important contribution

More information

Atomic Theory. Chapter 3. History of the Atom. Structure & Models of Atoms

Atomic Theory. Chapter 3. History of the Atom. Structure & Models of Atoms Chapter 3 Atoms Atomic Theory As early as 400 BC scientists have believed in an atomic theory thanks to Democritus. Atoms were the building blocks of matter. 2000 years later we can see the atom! History

More information

Unit 2 The Atom. Notes. 3. Describe Democritus thoughts about gold. 400 B.C. - Democritus thought matter could not be divided indefinitely.

Unit 2 The Atom. Notes. 3. Describe Democritus thoughts about gold. 400 B.C. - Democritus thought matter could not be divided indefinitely. Unit 2 The Atom Name: Key Block DEMOCRITUS 1. Was Democritus a scientist? NO Notes 2. In what time of history did he live? 400 BC 3. Describe Democritus thoughts about gold. 400 B.C. - Democritus thought

More information

1. According to the modern model of the atom, the nucleus of an atom is surrounded by one or more

1. According to the modern model of the atom, the nucleus of an atom is surrounded by one or more 1. According to the modern model of the atom, the nucleus of an atom is surrounded by one or more 8. The diagram below represents the nucleus of an atom. A) electrons B) neutrons C) positrons D) protons

More information

7.4. Using the Bohr Theory KNOW? Using the Bohr Theory to Describe Atoms and Ions

7.4. Using the Bohr Theory KNOW? Using the Bohr Theory to Describe Atoms and Ions 7.4 Using the Bohr Theory LEARNING TIP Models such as Figures 1 to 4, on pages 218 and 219, help you visualize scientific explanations. As you examine Figures 1 to 4, look back and forth between the diagrams

More information

Chapter 2 Atoms, Molecules, and Ions

Chapter 2 Atoms, Molecules, and Ions Chapter 2 Atoms, Molecules, and Ions 1. Methane and ethane are both made up of carbon and hydrogen. In methane, there are 12.0 g of carbon for every 4.00 g of hydrogen, a ration of 3:1 by mass. In ethane,

More information

Introductory Chemistry Fourth Edition Nivaldo J. Tro

Introductory Chemistry Fourth Edition Nivaldo J. Tro Introductory Chemistry Fourth Edition Nivaldo J. Tro Chapter 6 Chemical Composition Dr. Sylvia Esjornson Southwestern Oklahoma State University Weatherford, OK 6.1 How Much Sodium? Sodium is an important

More information

Atomic Theory: History of the Atom

Atomic Theory: History of the Atom Atomic Theory: History of the Atom Atomic Theory: experimental observations that led scientists to postulate the existence of the atom (smallest bit of an element). 1. Law of Conservation of Mass -During

More information

Periodic Table & Atomic Structure

Periodic Table & Atomic Structure St Peter the Apostle High School Chemistry Department Periodic Table & Atomic Structure N4 & N5 Homework Questions Answer questions as directed by your teacher. National 4 level questions are first followed

More information

2. John Dalton did his research work in which of the following countries? a. France b. Greece c. Russia d. England

2. John Dalton did his research work in which of the following countries? a. France b. Greece c. Russia d. England CHAPTER 3 1. Which combination of individual and contribution is not correct? a. Antoine Lavoisier - clarified confusion over cause of burning b. John Dalton - proposed atomic theory c. Marie Curie - discovered

More information

47374_04_p25-32.qxd 2/9/07 7:50 AM Page 25. 4 Atoms and Elements

47374_04_p25-32.qxd 2/9/07 7:50 AM Page 25. 4 Atoms and Elements 47374_04_p25-32.qxd 2/9/07 7:50 AM Page 25 4 Atoms and Elements 4.1 a. Cu b. Si c. K d. N e. Fe f. Ba g. Pb h. Sr 4.2 a. O b. Li c. S d. Al e. H f. Ne g. Sn h. Au 4.3 a. carbon b. chlorine c. iodine d.

More information

Chemical vs. Physical Changes: 1. How can we define a chemical change? Give example reaction equations.

Chemical vs. Physical Changes: 1. How can we define a chemical change? Give example reaction equations. Name: Teacher: Date: Period: Directions: Try to answer EVERY question on here. Some questions have multiple parts. If you are confused or want to check your answers you should attend SGI with this sheet!

More information

Atoms, Isotopes, and Ions

Atoms, Isotopes, and Ions WHY? ACTIVITY 02-1 Atoms, Isotopes, and Ions Atoms are the fundamental building blocks of all substances. To begin to understand the properties of atoms and how they combine to form molecules, you must

More information

Atoms, Molecules and Ions. In This Chapter

Atoms, Molecules and Ions. In This Chapter Atoms, Molecules and Ions Chapter 2 In This Chapter History of atoms. Subatomic particles. Atomic numbers, mass numbers. Isotopes and Atomic weights. Compounds, Molecules and Ions. Nomenclature. 2 1 Elements

More information

Chemistry: Atomic Structure

Chemistry: Atomic Structure Chemistry: Atomic Structure Organization of the Modern Periodic Table The periodic table is organized by properties. The Atom Today atom = All atoms of the same element are essentially (but not exactly)

More information

Chapter 3. Molecules, Compounds, and Chemical Composition

Chapter 3. Molecules, Compounds, and Chemical Composition Chapter 3 Molecules, Compounds, and Chemical Composition Elements and Compounds Elements combine together to make an almost limitless number of compounds. The properties of the compound are totally different

More information

Chapter 10 Chemical Quantities

Chapter 10 Chemical Quantities Chapter 10 Chemical Quantities 101 The Mole: A Measurement 102 Mole-Mass and Mole-Volume Relationships 103 Percent Composition and Chemical Formulas 1 Copyright Pearson Education, Inc, or its affiliates

More information

3 CHEMICAL FOUNDATIONS: ELEMENTS, ATOMS AND IONS

3 CHEMICAL FOUNDATIONS: ELEMENTS, ATOMS AND IONS 3 CHEMICAL FOUNDATIONS: ELEMENTS, ATOMS AND IONS All matter is built up from chemical combinations of elements. As of 2003, there are 114 known elements, of which 88 are naturally occurring; the remaining

More information

Chapter 4: Atoms and Elements

Chapter 4: Atoms and Elements Chapter 4 Page 1 Chapter 4: Atoms and Elements Atoms are EXTREMELY SMALL particles out of which all knownmatter is made. They are the smallest particle of a chemical element that still have the properties

More information

SAI. Protons Electrons Neutrons Isotope Name. Isotope Symbol 131i S3 1. Atomic Number. Mass Number

SAI. Protons Electrons Neutrons Isotope Name. Isotope Symbol 131i S3 1. Atomic Number. Mass Number ATOMIC STRUCTURE AND THE PERIODIC TABLE CHAPTER 4 WORKSHEET PART A Given the following isotopes, determine the atomic number, the mass number, the number of protons, electrons and neutrons. Isotope Symbol

More information

Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.

Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. Introduction to Chemistry Exam 2 Practice Problems 1 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1.Atoms consist principally of what three

More information

Atomic Theory: The Nuclear Model of the Atom

Atomic Theory: The Nuclear Model of the Atom Chapter 5 Atomic Theory: The Nuclear Model of the Atom Section 5.1 Dalton s Atomic Theory Goal 1 Precursors to John Dalton s atomic theory Law of Definite Composition The percentage by mass of the elements

More information

Chapter 5: Early Atomic Theory and Structure. 5.1 Early Thoughts. In the year 440 B.C., believed that all matter was made of 4 elements (list them):

Chapter 5: Early Atomic Theory and Structure. 5.1 Early Thoughts. In the year 440 B.C., believed that all matter was made of 4 elements (list them): Chapter 5: Early Atomic Theory and Structure Name: 5.1 Early Thoughts In the year 440 B.C., believed that all matter was made of 4 elements (list them): Around 370 B.C., proposed that all matter was composed

More information

Name Class Date ELECTRONS AND THE STRUCTURE OF ATOMS

Name Class Date ELECTRONS AND THE STRUCTURE OF ATOMS Atomic Structure ELECTRONS AND THE STRUCTURE OF ATOMS 4.1 Defining the Atom Essential Understanding Atoms are the fundamental building blocks of matter. Lesson Summary Early Models of the Atom The scientific

More information

Name: KEY Block: Date: Unit 2 Test Review

Name: KEY Block: Date: Unit 2 Test Review Name: KEY Block: Date: Unit 2 Test Review Matter and Atomic Structure Complete the following problems to help prepare you for you Unit 2 Test. You more than likely will want to answer these questions on

More information

3 large lures x 22.0 g/lure + 5 medium lures x 12.9 g/lure + 5 small lures x 8.5 g/lure g packaging = g

3 large lures x 22.0 g/lure + 5 medium lures x 12.9 g/lure + 5 small lures x 8.5 g/lure g packaging = g Answers additional questions 7.1 1. Describe how the particles of sodium bromide, an ionic compound, are different from water, a covalent compound. Give the particle name of each compound type. Ionic compounds

More information

Chapter 7. Bellringer. Table of Contents. Chapter 7. Chapter 7. Objectives. Avogadro s Number and the Mole. Chapter 7. Chapter 7

Chapter 7. Bellringer. Table of Contents. Chapter 7. Chapter 7. Objectives. Avogadro s Number and the Mole. Chapter 7. Chapter 7 The Mole and Chemical Table of Contents Chemical Formulas Bellringer List as many common counting units as you can. Determine how many groups of each unit in your list are present in each of the following

More information

The modern model of the atom is based on the work of

The modern model of the atom is based on the work of Atomic Structure The modern model of the atom is based on the work of A.) one scientist over a short period of time B.) one scientist over a long period of time C.) many scientists over a short period

More information

Isotopes. Isotopes are written with the name followed by a hyphen and the mass number. Symbol notation is when we write it like this: and O

Isotopes. Isotopes are written with the name followed by a hyphen and the mass number. Symbol notation is when we write it like this: and O Isotopes Isotopes are atoms of the same element that have different masses due to different numbers of neutrons. See the example below for two isotopes of oxygen. One has 8 neutrons while the other has

More information

CHAPTER 13 THE PERIODIC TABLE

CHAPTER 13 THE PERIODIC TABLE CHAPTER 13 THE PERIODIC TABLE OVERVIEW The periodic table is usually the first thing that comes to mind when thinking about the subject of chemistry. We have all heard about the periodic table from as

More information

The Structure of the Atom

The Structure of the Atom The Structure of the Atom Section 4.1 Early Ideas About Matter Section 4.2 Defining the Atom Section 4.3 How Atoms Differ Section 4.4 Unstable Nuclei and Radioactive Decay Click a hyperlink or folder tab

More information

Chemistry Summer School Pre-Test 2015

Chemistry Summer School Pre-Test 2015 NAME: 1. A material consists of pure sodium. How many types of atomic structures are present in this substance? (C.1.1) A. No atomic structures are present as this is a pure substance. B. One type of atomic

More information

Chapter 1: Moles and equations. Learning outcomes. you should be able to:

Chapter 1: Moles and equations. Learning outcomes. you should be able to: Chapter 1: Moles and equations 1 Learning outcomes you should be able to: define and use the terms: relative atomic mass, isotopic mass and formula mass based on the 12 C scale perform calculations, including

More information

Electrons in Atoms & Periodic Table Chapter 13 & 14 Assignment & Problem Set

Electrons in Atoms & Periodic Table Chapter 13 & 14 Assignment & Problem Set Electrons in Atoms & Periodic Table Name Warm-Ups (Show your work for credit) Date 1. Date 2. Date 3. Date 4. Date 5. Date 6. Date 7. Date 8. Electrons in Atoms & Periodic Table 2 Study Guide: Things You

More information

Physical Sciences: Matter & Energy. What is physical science? A. Physical science is a field of science that studies matter and energy.

Physical Sciences: Matter & Energy. What is physical science? A. Physical science is a field of science that studies matter and energy. Physical Sciences: Matter & Energy What is physical science? A. Physical science is a field of science that studies matter and energy. B. Physical science has 2 main branches: 1. PHYSICS: the study of

More information

TOPIC 7. CHEMICAL CALCULATIONS I - atomic and formula weights.

TOPIC 7. CHEMICAL CALCULATIONS I - atomic and formula weights. TOPIC 7. CHEMICAL CALCULATIONS I - atomic and formula weights. Atomic structure revisited. In Topic 2, atoms were described as ranging from the simplest atom, H, containing a single proton and usually

More information

The Structure of an Atom

The Structure of an Atom CP Biology 2016 Name KEY UNIT 2A: Basic Chemistry Chapter 2: The Chemistry of Life 2.1 The Nature of Matter The Structure of an Atom Living things share a major fundamental similarity with nonliving matter.

More information

Chapter 3 Atoms and Elements

Chapter 3 Atoms and Elements Chapter 3 Atoms and Elements 1 Elements Elements are pure substances that cannot be separated into simpler substances by ordinary laboratory processes the building blocks of matter listed on the inside

More information

Atomic Structure Chapter 5 Assignment & Problem Set

Atomic Structure Chapter 5 Assignment & Problem Set Atomic Structure Name Warm-Ups (Show your work for credit) Date 1. Date 2. Date 3. Date 4. Date 5. Date 6. Date 7. Date 8. Atomic Structure 2 Study Guide: Things You Must Know Vocabulary (know the definition

More information

Woods Chem-1 Lec-02 10-1 Atoms, Ions, Mole (std) Page 1 ATOMIC THEORY, MOLECULES, & IONS

Woods Chem-1 Lec-02 10-1 Atoms, Ions, Mole (std) Page 1 ATOMIC THEORY, MOLECULES, & IONS Woods Chem-1 Lec-02 10-1 Atoms, Ions, Mole (std) Page 1 ATOMIC THEORY, MOLECULES, & IONS Proton: A positively charged particle in the nucleus Atomic Number: We differentiate all elements by their number

More information

Mr. Dolgos Regents Chemistry NOTE PACKET. Unit 2: Atomic Theory

Mr. Dolgos Regents Chemistry NOTE PACKET. Unit 2: Atomic Theory *STUDENT* *STUDENT* Mr. Dolgos Regents Chemistry NOTE PACKET Unit 2: Atomic Theory 1 *STUDENT* UNIT 2 - ATOMIC THEORY *STUDENT* VOCABULARY: Allotrope Anion Atom Atomic Mass Atomic Mass unit (a.m.u.) Atomic

More information

EXPERIMENT 4: Electron Configuration of elements

EXPERIMENT 4: Electron Configuration of elements Material: laboratory display of the elements and a wall periodic table is required. Objective: To learn the use of periodic table for writing electron configuration of elements. INTRODUCTION Basic building

More information

IB Chemistry 1 Mole. One atom of C-12 has a mass of 12 amu. One mole of C-12 has a mass of 12 g. Grams we can use more easily.

IB Chemistry 1 Mole. One atom of C-12 has a mass of 12 amu. One mole of C-12 has a mass of 12 g. Grams we can use more easily. The Mole Atomic mass units and atoms are not convenient units to work with. The concept of the mole was invented. This was the number of atoms of carbon-12 that were needed to make 12 g of carbon. 1 mole

More information

Physical Science Notes Properties of Atoms and the Periodic Table

Physical Science Notes Properties of Atoms and the Periodic Table Physical Science Notes Properties of Atoms and the Periodic Table Structure of the Atom Elements are abbreviated in scientific shorthand. Symbols on the periodic table are short or abbreviated ways to

More information

Chemistry I Study Guideline Unit Three Atomic Structure

Chemistry I Study Guideline Unit Three Atomic Structure Chemistry I Study Guideline Unit Three Atomic Structure By the end of this chapter, you should be able to: 1. Describe the nature and significance of scientific modeling in general and several of the atoms

More information

Atomic Structure. Atoms and elements

Atomic Structure. Atoms and elements Atomic Structure Atoms and elements Everything in the world is made up from about 100 elements. Every element is made up of very small particles called atoms. An element is a substance in which all the

More information

BALANCING CHEMICAL EQUATIONS

BALANCING CHEMICAL EQUATIONS BALANCING CHEMICAL EQUATIONS The Conservation of Matter states that matter can neither be created nor destroyed, it just changes form. If this is the case then we must account for all of the atoms in a

More information

Iron is. Temperature is a(n) property of a substance. Select two that apply. Which of the following is a chemical change?

Iron is. Temperature is a(n) property of a substance. Select two that apply. Which of the following is a chemical change? Posting ID: 419903 Course: CHE 105 2015 SU Instructor: Sarah Edwards Question #: 1 Iron is. A. a compound B. a heterogenous mixture C. a homogenous mixture D. an element Question #: 2 Temperature is a(n)

More information

Page 1. Atomic Theory

Page 1. Atomic Theory About 440 B.C. Empedocles stated that all matter was composed of four "elements" earth, air, water, and fire. Democritus (460-370 BC) Theorized that all matter is composed of small indivisible particles

More information

1. Structure and Properties of the Atom

1. Structure and Properties of the Atom SACE Stage 1 Chemistry - The Essentials 1. Structure and Properties of the Atom 1.1 Atoms: A simple definition of the atom is that it is the smallest particle that contains the properties of that element.

More information

Calculating Atoms, Ions, or Molecules Using Moles

Calculating Atoms, Ions, or Molecules Using Moles TEKS REVIEW 8B Calculating Atoms, Ions, or Molecules Using Moles TEKS 8B READINESS Use the mole concept to calculate the number of atoms, ions, or molecules in a sample TEKS_TXT of material. Vocabulary

More information

6/27/2014. Periodic Table of the ELEMENTS. Chemical REACTIONS you should know. Brief Review for 1311 Honors Exam 2

6/27/2014. Periodic Table of the ELEMENTS. Chemical REACTIONS you should know. Brief Review for 1311 Honors Exam 2 Brief Review for 3 Honors Exam 2 Chapter 2: Periodic Table I. Metals. Representative Metals Alkali Metals Group Alkaline Earth Metals. Group 2 2. Transition Metals II. Metalloids Chapter 3: All Chapter

More information

More on ions (Chapters 2.1 and )

More on ions (Chapters 2.1 and ) More on ions (Chapters 2.1 and 3.5 3.7) Ion: an atom or molecule that has a net electrical charge. Examples: Na + (sodium ion), Cl - (chloride), NH 4 + (ammonium). Anion: a negative ion, formed when electrons

More information

Worked solutions to student book questions Chapter 2 A particle view of matter

Worked solutions to student book questions Chapter 2 A particle view of matter Q1. Dalton and Thomson each proposed a model of an atom. a What experimental evidence did Thomson have that was not available to Dalton? b As a result of this experimental evidence, how did Thomson s model

More information

Chemical Calculations: The Mole Concept and Chemical Formulas. AW Atomic weight (mass of the atom of an element) was determined by relative weights.

Chemical Calculations: The Mole Concept and Chemical Formulas. AW Atomic weight (mass of the atom of an element) was determined by relative weights. 1 Introduction to Chemistry Atomic Weights (Definitions) Chemical Calculations: The Mole Concept and Chemical Formulas AW Atomic weight (mass of the atom of an element) was determined by relative weights.

More information

A technician using a scanner to monitor the uptake of radioactive iodine in a patient s thyroid. P.48

A technician using a scanner to monitor the uptake of radioactive iodine in a patient s thyroid. P.48 A technician using a scanner to monitor the uptake of radioactive iodine in a patient s thyroid. P.48 Rodioactivity In the late nineteenth century scientists discovered that certain elements produce high-energy

More information

Chapter 3 Applying Your Knowledge- Even Numbered

Chapter 3 Applying Your Knowledge- Even Numbered Chapter 3 Applying Your Knowledge- Even Numbered 2. Elements in a specific compound are always present in a definite proportion by mass; for example, in methane, CH 4, 12 g of carbon are combined with

More information

History of the Atom & Atomic Theory

History of the Atom & Atomic Theory Chapter 5 History of the Atom & Atomic Theory You re invited to a Thinking Inside the Box Conference Each group should nominate a: o Leader o Writer o Presenter You have 5 minutes to come up with observations

More information

Chemistry Final Exam Review

Chemistry Final Exam Review Name: Date: Block: Chemistry Final Exam Review 2012-2013 Unit 1: Measurement, Numbers, Scientific Notation, Conversions, Dimensional Analysis 1. Write 0.000008732 in scientific notation 8.732x10-6 2. Write

More information

Chapter 5 Atomic Structure and the Periodic Table. Section 5.1 Atoms

Chapter 5 Atomic Structure and the Periodic Table. Section 5.1 Atoms Chapter 5 Atomic Structure and the Periodic Table Section 5.1 Atoms OBJECTIVES: Summarize Dalton s atomic theory. Describe the size of an atom. Adapted from notes by Stephen L. Cotton History of the atom

More information