Chapter 3: ex. P2O5 molecular mass = 2(30.97 amu) + 5(16.00 amu) = amu


 Grant Blankenship
 2 years ago
 Views:
Transcription
1 Molecular Mass and Formula Mass for molecular compounds: the molecular mass is the mass (in amu) of one molecule of the compound molecular mass = atomic masses of elements present Chapter 3: ex. P2O5 molecular mass = 2(30.97 amu) + 5(16.00 amu) = amu Calculations with Chemical Formulas and Equations for ionic compounds: the formula mass is the mass (in amu) of one formula unit of the compound formula mass = atomic masses of elements present ex. Ca(ClO3)2 formula mass = amu + 2(35.45 amu) + 6(16.00 amu) = amu The Mole Using NA as a Conversion Factor SI base unit for amount of substance the mole is a counting unit 1 mole contains the same number of particles as there are atoms in exactly 12 g of 12C by definition: 1mol = x particles Avogadro s number, NA = x 1023 mol!1 so: 1 mol Li = x 1023 Li atoms NA relates amount of substance in mol to number of particles* * particles may be atoms, molecules, formula units or ions depending on sample under consideration examples: Calculate the amount (in mol) of molybdenum in a sample containing x 1025 atoms Mo. 1 mol H2O = x 1023 H2O molecules 1 mol NaNO3 = x 1023 NaNO3 formula units Calculate the number of SO3 molecules in 1.25 mol SO3.
2 Molar Mass What Does 1 Mole Look Like? Molar Mass of an Element  mass (in g) per mole of an element. units g/mol Molar Mass of a Compound  mass (in g) per mole of a compound. units g/mol molar mass compound = molar mass of elements present Molar Mass of an Element Molar Mass of an Element calculate the molar mass of an element: ex: Determine the mass (in g) of mol Sn. convert average atomic mass (in amu/atom) to molar mass (in g/mol) ex: Determine the molar mass of rhodium. use molar mass as a conversion factor relating sample mass (in g) to amount of substance (in mol) combine molar mass and NA as conversion factors... ex: Determine the number of atoms in g Sn. ex: Determine the mass (in g) of a single atom of Sn.
3 Molar Mass of a Compound Molar Mass of a Compound  mass (in g) per mole of a compound. units g/mol molar mass compound = molar mass of elements present ex: Calculate the molar mass of phosphorus pentachloride. ex: Calculate the number of molecules in 10.0 mg PCl5. ex: Calculate the mass (in g) of a single PCl5 molecule. Compound Stoichiometry the subscripts in a chemical formula tell us the ratio of how elements combine use these ratios as conversion factors in calculations ex: Consider calcium nitrate. Write the chemical formula. What relationships exist between... mass in g mass in amu amount in mol # of formula units # of calcium ions # of nitrate ions mol of calcium ion mol of nitrate ion # s of Ca, N, and O atom mol of Ca, N, and O Compound Stoichiometry Calculations Consider a 25.0 g sample of Ca(NO3)2. Determine the following: a. molar mass b. mol Ca(NO3)2 c. mol Ca 2+ d. mol NO3! e. mass (in g) of O f. number of NO3! ions g. number of formula units h. number of O atoms i. mass (in g) of 1 formula unit Mass Percent Composition composition of compound with respect to percent mass of each element present consider AxBy: x(molar mass A) mass% A = x 100 molar mass AxBy y(molar mass B) mass% B = x 100 molar mass AxBy and: mass % A + mass % B = 100% ex: Determine the mass % composition of barium nitrate.
4 Chemical Formulas: Empirical Formula vs. Molecular Formula empirical formula: relative numbers of atoms present subscripts in chemical formula are smallest possible whole number ratio molecular formula: exact numbers of atoms present subscripts in chemical formula may or may not be smallest possible whole number ratio Determination of Empirical and Molecular Formulas: Using Mass Percent Composition Data ex: Vitamin C (molar mass = g/mol) is composed of 40.9% C, 4.57% H, and 54.5% O by mass. Determine the empirical and molecular formula of Vitamin C. 1. Determine the mol of each element present. assume a 100 g sample and use mass % composition to interpret g of each element present convert g element! mol element 2. Determine the mol ratio of elements present in the smallest whole numbers. Determination of Empirical and Molecular Formulas: Using Mass Percent Composition Data (Cont d) ex: Vitamin C (molar mass = g/mol) is composed of 40.9% C, 4.57% H, and 54.5% O by mass. Determine the empirical and molecular formula of Vitamin C. 3. Divide the actual molar mass of the compound by the molar mass of the empirical formula. This will equal a small whole number, n. 4. Multiply the subscripts of the empirical formula by n! molecular formula
5 Another Formula Determination Example: Stoichiometry of Chemical Reactions A mg sample of a compound composed of only cadmium and phosphorus is analyzed and found to contain mg Cd. Answer questions like: Determine the empirical and molecular formulas of this compound. The actual molar mass of the compound is g/mol. Consider the reaction: CaO (s) + 3 C (s) " CaC2 (s) + CO (g) g/mol g/mol g/mol g/mol Calculate the mass (in g) of C required to react completely with g CaO. How many g of reactant B are required to react completely with x g of reactant A? How many g of product C can be formed from the complete reaction of x g of reactant A? Reaction Yields theoretical yield: maximum amount of product that can form in a reaction; typically reported in g or mol Calculate the mass (in g) of CaC2 that can form from the complete reaction of g CaO. 1 actual or experimental yield: actual amount of product collected from a reaction percent yield: percentage of the theoretical yield that is actually collected actual yield % yield = " 100 theoretical yield
6 Identification of the Limiting Reactant The limiting reactant is the reactant that limits the theoretical yield of product. it is the reactant that is completely consumed during the course of the chemical reaction as soon as one of the reactants is gone, the reaction must stop! TO CALCULATE A THEORETICAL YIELD, YOU MUST ALWAYS START WITH THE LIMITING REACTANT!! Identification of the Limiting Reactant: (a not very scientific example) to build a perfect s more you need: 2 graham crackers 2 marshmallows 1 square of chocolate Consider 2 sets of ingredients: A 50 graham crackers 50 marshmallows 25 squares chocolate B 60 graham crackers 75 marshmallows 22 squares chocolate Identification of the Limiting Reactant: (a not very scientific example) set up s more reaction tables: 2 graham crackers + 2 marshmallows + 1 square chocolate " 1 s more before change after graham crackers + 2 marshmallows + 1 square chocolate " 1 s more before change after Identification of Limiting Reactant: Calculations and Reaction Tables 100 g CaC2 and 100 g H2O are combined and allowed to react. identify the limiting reactant calculate the theoretical yield of products determine the mass of the excess reactant that remains unconsumed when the reaction is complete complete the reaction table
7 Calculations to fill in the reaction table: determine mol of each reactant 1 mol CaC2 100 g CaC2 " = 1.56 mol CaC g 1 mol H2O 100 g H2O " = 5.55 mol H2O g Calculations to fill in the reaction table: pick one reactant; calculate mol of 2 nd reactant required to react completely with the 1 st reactant 2 mol H2O 1.56 mol CaC2 " = 3.12 mol H2O 1 mol CaC2 or conversely 1 mol CaC mol H2O " = 2.78 mol CaC2 2 mol H2O Calculations to fill in the reaction table: compare mol of 2 nd reactant required for complete reaction to mol present in the system here  more H2O is present (5.55 mol) than is required (3.12 mol) to completely consume CaC2 H2O is the excess reactant OR there is less CaC2 present (1.56 mol) than is required (2.78 mol) to completely consume H2O present CaC2 is the limiting reactant before 1.56 mol 5.55 mol 0 0 change!1.56 mol!3.12 mol mol mol after mol 1.56 mol 1.56 mol before 1.56 mol 5.55 mol 0 0 change!1.56 mol!(2 1)1.56 mol +(1 1)1.56 mol +(1 1)1.56 mol after mol 1.56 mol 1.56 mol
8 Calculations based on the reaction table: determine the theoretical yield of each product g 1.56 mol Ca(OH)2 " = 116 g Ca(OH)2 1 mol Ca(OH) g 1.56 mol C2H2 " = 40.6 g C2H2 1 mol C2H2 determine the mass of excess reactant unconsumed when the reaction is complete Homework Problem: TiO2 (s) + 4 C (s) + 6 Cl2 (g)! 3 TiCl4 (g) + 2 CO2 (g) + 2 CO (g) 4.15 g 5.67 g 6.78 g g/mol g/mol g/mol 3 TiO2 + 4 C + 6 Cl2! 3 TiCl4 + 2 CO2 + 2 CO before mol mol mol change after g 2.43 mol H2O " = 43.8 g H2O 1 mol H2O A Final Reaction Stoichiometry Example: Gravimetric Analysis A g sample containing some unknown amount of potassium superoxide (KO2) and other substances is treated with excess H2O; the following reaction occurs * : 4 KO2 (s) + 2 H2O (l) " 4 KOH (s) + 3 O2 (g) *note: of the substances present in the original sample, only the KO2 will react with water Assuming that the you achieve complete conversion of KO2 to KOH, determine the mass percent KO2 in the original sample if the experiment yields g KOH.
The Mole Concept. The Mole. Masses of molecules
The Mole Concept Ron Robertson r2 c:\files\courses\111020\2010 final slides for web\mole concept.docx The Mole The mole is a unit of measurement equal to 6.022 x 10 23 things (to 4 sf) just like there
More informationHow much does a single atom weigh? Different elements weigh different amounts related to what makes them unique.
How much does a single atom weigh? Different elements weigh different amounts related to what makes them unique. What units do we use to define the weight of an atom? amu units of atomic weight. (atomic
More informationFormulas, Equations, and Moles. + "reacts with" "to produce" Equations must be balanced. Equal amounts of each element on each side of the equation.
Chapter 3 Formulas, Equations, and Moles Chemical Equations 2 2 + 2 2 2 reactants products + "reacts with" "to produce" coefficients  indicate amount of substance Equations must be balanced. Equal amounts
More informationFormula Stoichiometry. Text pages
Formula Stoichiometry Text pages 237250 Formula Mass Review Write a chemical formula for the compound. H 2 CO 3 Look up the average atomic mass for each of the elements. H = 1.008 C= 12.01 O = 16.00 Multiply
More informationChapter 3 Chemical Reactions and Reaction Stoichiometry. 許富銀 ( Hsu FuYin)
Chapter 3 Chemical Reactions and Reaction Stoichiometry 許富銀 ( Hsu FuYin) 1 Stoichiometry The study of the numerical relationship between chemical quantities in a chemical reaction is called stoichiometry.
More information1. How many hydrogen atoms are in 1.00 g of hydrogen?
MOLES AND CALCULATIONS USING THE MOLE CONCEPT INTRODUCTORY TERMS A. What is an amu? 1.66 x 1024 g B. We need a conversion to the macroscopic world. 1. How many hydrogen atoms are in 1.00 g of hydrogen?
More informationBalance the following equation: KClO 3 + C 12 H 22 O 11 KCl + CO 2 + H 2 O
Balance the following equation: KClO 3 + C 12 H 22 O 11 KCl + CO 2 + H 2 O Ans: 8 KClO 3 + C 12 H 22 O 11 8 KCl + 12 CO 2 + 11 H 2 O 3.2 Chemical Symbols at Different levels Chemical symbols represent
More informationChapter 7 Part II: Chemical Formulas and Equations. Mr. Chumbley Chemistry 12
Chapter 7 Part II: Chemical Formulas and Equations Mr. Chumbley Chemistry 12 SECTION 3: USING CHEMICAL FORMULAS Molecules and Formula Unit We have not yet discussed the different ways in which chemical
More informationChapter 3. Chemical Reactions and Reaction Stoichiometry. Lecture Presentation. James F. Kirby Quinnipiac University Hamden, CT
Lecture Presentation Chapter 3 Chemical Reactions and Reaction James F. Kirby Quinnipiac University Hamden, CT The study of the mass relationships in chemistry Based on the Law of Conservation of Mass
More information10 Cl atoms. 10 H2O molecules. 8.3 mol HCN = 8.3 mol N atoms 1 mol HCN. 2 mol H atoms 2.63 mol CH2O = 5.26 mol H atoms 1 mol CH O
Chem 100 Mole conversions and stoichiometry worksheet 1. How many Ag atoms are in.4 mol Ag atoms? 6.0 10 Ag atoms 4.4 mol Ag atoms = 1.46 10 Ag atoms 1 mol Ag atoms. How many Br molecules are in 18. mol
More informationChapter 3: Stoichiometry
Chapter 3: Stoichiometry Key Skills: Balance chemical equations Predict the products of simple combination, decomposition, and combustion reactions. Calculate formula weights Convert grams to moles and
More informationAP Chemistry. Unit #3. Chapter 3 Zumdahl
AP Chemistry Unit #3 Chapter 3 Zumdahl Stoichiometry C6H12O6 + 6 O2 6 CO2 + 6 H2O Students should be able to: Calculate the atomic weight (average atomic mass) of an element from the relative abundances
More informationChemical 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 informationCHEMISTRY CP Name: KEY Period: UNIT 5: TEST REVIEW SHEET MOLE CONVERSIONS, EMPIRICAL/MOLECULAR FORMULA, STOICHIOMETRY
CHEMISTRY CP Name: KEY Period: UNIT 5: TEST REVIEW SHEET MOLE CONVERSIONS, EMPIRICAL/MOLECULAR FORMULA, STOICHIOMETRY MOLES AND MOLE CONVERSIONS 1. Things to Know: a. What is a mole? Avogadro s number
More information= 16.00 amu. = 39.10 amu
Using Chemical Formulas Objective 1: Calculate the formula mass or molar mass of any given compound. The Formula Mass of any molecule, formula unit, or ion is the sum of the average atomic masses of all
More informationElement of same atomic number, but different atomic mass o Example: Hydrogen
Atomic mass: p + = protons; e  = electrons; n 0 = neutrons p + + n 0 = atomic mass o For carbon12, 6p + + 6n 0 = atomic mass of 12.0 o For chlorine35, 17p + + 18n 0 = atomic mass of 35.0 atomic mass
More informationCHAPTER 3 STOICHIOMETRY OF FORMULAS AND EQUATIONS
CHAPTER 3 STOICHIOMETRY OF FORMULAS AND EQUATIONS FOLLOW UP PROBLEMS 3.1A Plan: The mass of carbon must be changed from mg to g. The molar mass of carbon can then be used to determine the number of moles.
More informationCalculating 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 informationThe Mole Concept and Atoms
Copyright The McGrawHill Companies, Inc. Permission required for reproduction or display. Chapter 4 24 September 2013 Calculations and the Chemical Equation The Mole Concept and Atoms Atoms are exceedingly
More informationThe Mole. 6.022 x 10 23
The Mole 6.022 x 10 23 Background: atomic masses Look at the atomic masses on the periodic table. What do these represent? E.g. the atomic mass of Carbon is 12.01 (atomic # is 6) We know there are 6 protons
More informationFormulas, Equations and Moles
Chapter 3 Formulas, Equations and Moles Interpreting Chemical Equations You can interpret a balanced chemical equation in many ways. On a microscopic level, two molecules of H 2 react with one molecule
More informationCh. 10 The Mole I. Molar Conversions
Ch. 10 The Mole I. Molar Conversions I II III IV A. What is the Mole? A counting number (like a dozen) Avogadro s number (N A ) 1 mole = 6.022 10 23 representative particles B. Mole/Particle Conversions
More informationChemistry 65 Chapter 6 THE MOLE CONCEPT
THE MOLE CONCEPT Chemists find it more convenient to use mass relationships in the laboratory, while chemical reactions depend on the number of atoms present. In order to relate the mass and number of
More informationCHAPTER 3 Calculations with Chemical Formulas and Equations. atoms in a FORMULA UNIT
CHAPTER 3 Calculations with Chemical Formulas and Equations MOLECULAR WEIGHT (M. W.) Sum of the Atomic Weights of all atoms in a MOLECULE of a substance. FORMULA WEIGHT (F. W.) Sum of the atomic Weights
More informationChemical Equations and Calculations
Chemical Equations and Calculations A chemical equation is a shorthand way of indicating what is going on in a chemical reaction. We could do it the long way Two molecules of Hydrogen gas react with one
More informationTUTORIAL 51 HELP. Mass of sodium = 23.0 g/mol x 3 mol = 69.0 g of sodium. Percent mass of sodium = 69.0 g x 100% = 42.
TUTORIAL 51 HELP ANSWER TO QUESTION 1 ON TUTORIAL 51: Question 1. Find the percent composition by mass of sodium phosphate, Na 3 PO 4. Step 1: Find the molar mass of Na 3 PO 4 (The mass of one mole of
More informationChapter 3! Stoichiometry: Calculations with Chemical Formulas and Equations. Stoichiometry
Chapter 3! : Calculations with Chemical Formulas and Equations Anatomy of a Chemical Equation CH 4 (g) + 2O 2 (g) CO 2 (g) + 2 H 2 O (g) Anatomy of a Chemical Equation CH 4 (g) + 2 O 2 (g) CO 2 (g) + 2
More informationStoichiometry Dr. M. E. Bridge
Preliminary Chemistry Course Stoichiometry Dr. M. E. Bridge What is stoichiometry? The meaning of the word: The word stoichiometry comes from two Greek words: (meaning element ) and (meaning measure )
More informationThe Mole Notes. There are many ways to or measure things. In Chemistry we also have special ways to count and measure things, one of which is the.
The Mole Notes I. Introduction There are many ways to or measure things. In Chemistry we also have special ways to count and measure things, one of which is the. A. The Mole (mol) Recall that atoms of
More informationPart One: Mass and Moles of Substance. Molecular Mass = sum of the Atomic Masses in a molecule
CHAPTER THREE: CALCULATIONS WITH CHEMICAL FORMULAS AND EQUATIONS Part One: Mass and Moles of Substance A. Molecular Mass and Formula Mass. (Section 3.1) 1. Just as we can talk about mass of one atom of
More informationStoichiometry. What is the atomic mass for carbon? For zinc?
Stoichiometry Atomic Mass (atomic weight) Atoms are so small, it is difficult to discuss how much they weigh in grams We use atomic mass units an atomic mass unit (AMU) is one twelfth the mass of the catbon12
More informationOther Stoich Calculations A. mole mass (mass mole) calculations. GIVEN mol A x CE mol B. PT g A CE mol A MOLE MASS :
Chem. I Notes Ch. 12, part 2 Using Moles NOTE: Vocabulary terms are in boldface and underlined. Supporting details are in italics. 1 MOLE = 6.02 x 10 23 representative particles (representative particles
More informationStoichiometry. Lecture Examples Answer Key
Stoichiometry Lecture Examples Answer Key Ex. 1 Balance the following chemical equations: 3 NaBr + 1 H 3 PO 4 3 HBr + 1 Na 3 PO 4 2 C 3 H 5 N 3 O 9 6 CO 2 + 3 N 2 + 5 H 2 O + 9 O 2 2 Ca(OH) 2 + 2 SO 2
More informationPercent composition (mass percent, percent composition by mass)
Percent composition (mass percent, percent composition by mass) Mass % = mass of component in substance (grams) x 100 mass of substance (grams) What is the mass % composition of water? MM (H 2 O) = 18.0152
More informationPercent Composition 
Percent Composition  Percent Composition  % by mass of each element in a compound. Percent Composition  % by mass of each element in a compound. Example: MgCl2 Percent Composition  % by mass of each
More informationStudy Guide For Chapter 7
Name: Class: Date: ID: A Study Guide For Chapter 7 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The number of atoms in a mole of any pure substance
More informationThe mass of the formula unit is called the formula mass Formula masses are calculated the same way as molecular masses
Chapter 4: The Mole Atomic mass provides a means to count atoms by measuring the mass of a sample The periodic table on the inside cover of the text gives atomic masses of the elements The mass of an atom
More informationChapter 4 Chemical Composition. Moles of Various Elements and Compounds Figure 4.8
Chapter 4 Chemical Composition Mole Quantities Moles, Masses, and Particles Determining Empirical and Molecular Formulas Chemical Composition of Solutions 41 Copyright The McGrawHill Companies, Inc.
More informationChapter 3 Stoichiometry: Calculations with Chemical Formulas and Equations
CHE11 Chapter Chapter Stoichiometry: Calculations with Chemical Formulas and Equations 1. When the following equation is balanced, the coefficients are. NH (g) + O (g) NO (g) + H O (g) (a). 1, 1, 1, 1
More informationCHEMICAL FORMULA COEFFICIENTS AND SUBSCRIPTS. Chapter 3: Molecular analysis 3O 2 2O 3
Chapter 3: Molecular analysis Read: BLB 3.3 3.5 H W : BLB 3:21a, c, e, f, 25, 29, 37,49, 51, 53 Supplemental 3:1 8 CHEMICAL FORMULA Formula that gives the TOTAL number of elements in a molecule or formula
More informationSuggested Resources Textbook: Chapter 6 (6.3, 6.4, 6.5 & 6.6)
The Mole Big Picture Ideas: 1. The mole is a unit of count. 2. Using conversion factors, one can convert between mass, moles, particles and volume for a given substance. 3. Empirical data including percent
More informationChemistry I: Using Chemical Formulas. Formula Mass The sum of the average atomic masses of all elements in the compound. Units are amu.
Chemistry I: Using Chemical Formulas Formula Mass The sum of the average atomic masses of all elements in the compound. Units are amu. Molar Mass  The mass in grams of 1 mole of a substance. Substance
More informationChemical Reactions. Chemical Equations. Mole as Conversion Factor: To convert between number of particles and an equivalent number of moles:
Quantities of Reactants and Products CHAPTER 3 Chemical Reactions Stoichiometry Application of The Law of Conservation of Matter Chemical bookkeeping Chemical Equations Chemical equations: Describe proportions
More informationThe Mole, Avogadro s Number, and Molar Mass
The Mole, Avogadro s Number, and Molar Mass Example: How many atoms are present in 2.0 kg of silver? (1 amu = 1.6605402x1024 g) Example: How many molecules are present in 10. mg of smelling salts, (NH
More informationPERIODIC TABLE OF ELEMENTS. 4/23/14 Chapter 7: Chemical Reactions 1
PERIODIC TABLE OF ELEMENTS 4/23/14 Chapter 7: Chemical Reactions 1 CHAPTER 7: CHEMICAL REACTIONS 7.1 Describing Reactions 7.2 Types of Reactions 7.3 Energy Changes in Reactions 7.4 Reaction Rates 7.5 Equilibrium
More informationChapter 6 Chemical Composition
Chapter 6 Chemical Composition 1. 100 washers 0.110 g 1 washer = 11.0 g (assuming 100 washers is exact) 100. g 1 washer 0.110 g = 909 washers 2. 500. g 1 cork 1.63 g = 306.7 = 307 corks 500. g 1 stopper
More informationMass and Moles of a Substance
Chapter Three Calculations with Chemical Formulas and Equations Mass and Moles of a Substance Chemistry requires a method for determining the numbers of molecules in a given mass of a substance. This allows
More informationCHEMISTRY. (i) It failed to explain how atoms of different elements differ from each other.
CHEMISTRY MOLE CONCEPT DALTON S ATOMIC THEORY By observing the laws of chemical combination, John Dalton proposed an atomic theory of matter. The main points of Dalton s atomic theory are as follows: (i)
More informationCh. 6 Chemical Composition and Stoichiometry
Ch. 6 Chemical Composition and Stoichiometry The Mole Concept [6.2, 6.3] Conversions between g mol atoms [6.3, 6.4, 6.5] Mass Percent [6.6, 6.7] Empirical and Molecular Formula [6.8, 6.9] Bring your calculators!
More informationChapter 7. Chapter 7. Chemical Formulas Express Composition. Chapter 7 MARCH REVIEW SLIDES LISTEN AND UPDATE MISSING NOTES
REVIEW Express A compound s chemical formula tells you which elements, & how much of each, are present in a compound. Formulas for covalent compounds show the elements and the number of atoms of each element
More informationChem 115 POGIL Worksheet  Week 4 Moles & Stoichiometry
Chem 115 POGIL Worksheet  Week 4 Moles & Stoichiometry Why? Chemists are concerned with mass relationships in chemical reactions, usually run on a macroscopic scale (grams, kilograms, etc.). To deal with
More informationCHEMICAL QUANTITIES. Chapter 10
CHEMICAL QUANTITIES Chapter 10 What is a mole? A unit of measurement in chemistry 1 mole of a substance = 6.02 x 10 23 (Avagadro s number) representative particles of a substance Representative particle
More informationChem 31 Fall 2002. Chapter 3. Stoichiometry: Calculations with Chemical Formulas and Equations. Writing and Balancing Chemical Equations
Chem 31 Fall 2002 Chapter 3 Stoichiometry: Calculations with Chemical Formulas and Equations Writing and Balancing Chemical Equations 1. Write Equation in Words you cannot write an equation unless you
More informationUnit 5 Chemical Quantities & The Mole
Unit 5 Chemical Quantities & The Mole Molar mass is the mass of one mole of a substance. Molar Mass Other names for molar mass include *formula mass *gram formula mass *molecular weight Molar Mass One
More informationChem. Ch. 10 ~ THE MOLE NOTE: Vocabulary terms are in boldface and underlined. Supporting details are in italics.
Chem. Ch. 10 ~ THE MOLE NOTE: Vocabulary terms are in boldface and underlined. Supporting details are in italics. 10.1 Notes I. Measuring Matter A. SI unit of chemical quantity = the mole (abbreviated
More informationChapter 3. Stoichiometry of Formulas and Equations
Chapter 3 Stoichiometry of Formulas and Equations Chapter 3 Outline: Mole  Mass Relationships in Chemical Systems 3.1 The Mole 3.2 Determining the Formula of an Unknown Compound 3.3 Writing and Balancing
More informationWe know from the information given that we have an equal mass of each compound, but no real numbers to plug in and find moles. So what can we do?
How do we figure this out? We know that: 1) the number of oxygen atoms can be found by using Avogadro s number, if we know the moles of oxygen atoms; 2) the number of moles of oxygen atoms can be found
More informationMole  Mass Relationships in Chemical Systems
Chapter 3: Stoichiometry Mole  Mass Relationships in Chemical Systems 3.1 The Mole 3.2 Determining the Formula of an Unknown Compound 3.3 Writing and Balancing Chemical Equations 3.4 Calculating the Amounts
More informationCalculations and Chemical Equations. Example: Hydrogen atomic weight = 1.008 amu Carbon atomic weight = 12.001 amu
Calculations and Chemical Equations Atomic mass: Mass of an atom of an element, expressed in atomic mass units Atomic mass unit (amu): 1.661 x 1024 g Atomic weight: Average mass of all isotopes of a given
More informationStoichiometry. Types of Problems. Stoichiometry. Chemistry 1010 Review Tutorial 4/9/2013. Stoichiometry and Lewis Structures
Stoichiometry Chemistry 1010 Review Tutorial Stoichiometry and Lewis Structures April 9 th, 2013 Stoichiometry Stoichiometry involves MOLES Elements/compounds can only be compared side by side using moles
More informationPractice questions for Ch. 3
Name: Class: Date: ID: A Practice questions for Ch. 3 1. A hypothetical element consists of two isotopes of masses 69.95 amu and 71.95 amu with abundances of 25.7% and 74.3%, respectively. What is the
More informationUnit 2. Molar Mass Worksheet
Unit 2 Molar Mass Worksheet Calculate the molar masses of the following chemicals: 1) Cl 2 8) UF 6 2) KOH 9) SO 2 3) BeCl 2 10) H 3 PO 4 4) FeCl 3 11) (NH 4 ) 2 SO 4 5) BF 3 12) CH 3 COOH 6) CCl 2 F 2
More informationIB Chemistry 1 Mole. One atom of C12 has a mass of 12 amu. One mole of C12 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 carbon12 that were needed to make 12 g of carbon. 1 mole
More informationChapter 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 informationChemical Composition. Introductory Chemistry: A Foundation FOURTH EDITION. Atomic Masses. Atomic Masses. Atomic Masses. Chapter 8
Introductory Chemistry: A Foundation FOURTH EDITION by Steven S. Zumdahl University of Illinois Chemical Composition Chapter 8 1 2 Atomic Masses Balanced equation tells us the relative numbers of molecules
More informationChapter 3. Stoichiometry: Ratios of Combination. Insert picture from First page of chapter. Copyright McGrawHill 2009 1
Chapter 3 Insert picture from First page of chapter Stoichiometry: Ratios of Combination Copyright McGrawHill 2009 1 3.1 Molecular and Formula Masses Molecular mass  (molecular weight) The mass in amu
More informationChapter 4 Chemical Composition
Chapter 4 Chemical Composition 4.1 (a) mole; (b) Avogadro s number; (c) empirical formula; (d) solute; (e) molarity; (f) concentrated solution 4. (a) molar mass; (b) percent composition by mass; (c) solvent;
More information2 Stoichiometry: Chemical Arithmetic Formula Conventions (1 of 24) 2 Stoichiometry: Chemical Arithmetic Stoichiometry Terms (2 of 24)
Formula Conventions (1 of 24) Superscripts used to show the charges on ions Mg 2+ the 2 means a 2+ charge (lost 2 electrons) Subscripts used to show numbers of atoms in a formula unit H 2 SO 4 two H s,
More informationStoichiometry. Web Resources Chem Team Chem Team Stoichiometry. Section 1: Definitions Define the following terms. Average Atomic mass  Molecule 
Web Resources Chem Team Chem Team Section 1: Definitions Define the following terms Average Atomic mass  Molecule  Molecular mass  Moles  Avagadro's Number  Conservation of matter  Percent composition
More informationChapter 4. Chemical Composition. Chapter 4 Topics H 2 S. 4.1 Mole Quantities. The Mole Scale. Molar Mass The Mass of 1 Mole
Chapter 4 Chemical Composition Chapter 4 Topics 1. Mole Quantities 2. Moles, Masses, and Particles 3. Determining Empirical Formulas 4. Chemical Composition of Solutions Copyright The McGrawHill Companies,
More informationLecture 5, The Mole. What is a mole?
Lecture 5, The Mole What is a mole? Moles Atomic mass unit and the mole amu definition: 12 C = 12 amu. The atomic mass unit is defined this way. 1 amu = 1.6605 x 1024 g How many 12 C atoms weigh 12 g?
More informationChemistry B11 Chapter 4 Chemical reactions
Chemistry B11 Chapter 4 Chemical reactions Chemical reactions are classified into five groups: A + B AB Synthesis reactions (Combination) H + O H O AB A + B Decomposition reactions (Analysis) NaCl Na +Cl
More informationLiquid phase. Balance equation Moles A Stoic. coefficient. Aqueous phase
STOICHIOMETRY Objective The purpose of this exercise is to give you some practice on some Stoichiometry calculations. Discussion The molecular mass of a compound is the sum of the atomic masses of all
More information10 The Mole. Section 10.1 Measuring Matter
Name Date Class The Mole Section.1 Measuring Matter In your textbook, read about counting particles. In Column B, rank the quantities from Column A from smallest to largest. Column A Column B 0.5 mol 1.
More informationMOLECULAR MASS AND FORMULA MASS
1 MOLECULAR MASS AND FORMULA MASS Molecular mass = sum of the atomic weights of all atoms in the molecule. Formula mass = sum of the atomic weights of all atoms in the formula unit. 2 MOLECULAR MASS AND
More informationChemical Calculations: Formula Masses, Moles, and Chemical Equations
Chemical Calculations: Formula Masses, Moles, and Chemical Equations Atomic Mass & Formula Mass Recall from Chapter Three that the average mass of an atom of a given element can be found on the periodic
More informationSubscripts and Coefficients Give Different Information
Chapter 3: Stoichiometry Goal is to understand and become proficient at working with: 1. Chemical equations (Balancing REVIEW) 2. Some simple patterns of reactivity 3. Formula weights (REVIEW) 4. Avogadro's
More informationCHAPTER 8: CHEMICAL COMPOSITION
CHAPTER 8: CHEMICAL COMPOSITION Active Learning: 14, 68, 12, 1825; EndofChapter Problems: 34, 982, 8485, 8792, 94104, 107109, 111, 113, 119, 125126 8.2 ATOMIC MASSES: COUNTING ATOMS BY WEIGHING
More informationChapter 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 informationName Date Class CHEMICAL QUANTITIES. SECTION 10.1 THE MOLE: A MEASUREMENT OF MATTER (pages 287 296)
Name Date Class 10 CHEMICAL QUANTITIES SECTION 10.1 THE MOLE: A MEASUREMENT OF MATTER (pages 287 296) This section defines the mole and explains how the mole is used to measure matter. It also teaches
More informationCHAPTER 11  CHEMICAL QUANTITIES
I. THE MOLE CONCEPT CHAPTER 11  CHEMICAL QUANTITIES A. What is a mole? 1. a mole is the SI unit of measurement of counting; just like a dozen is a measurement 2. a mole is a number a. 6.02 x 10 23 is
More informationChapter 1 The Atomic Nature of Matter
Chapter 1 The Atomic Nature of Matter 6. Substances that cannot be decomposed into two or more simpler substances by chemical means are called a. pure substances. b. compounds. c. molecules. d. elements.
More informationMole Notes.notebook. October 29, 2014
1 2 How do chemists count atoms/formula units/molecules? How do we go from the atomic scale to the scale of everyday measurements (macroscopic scale)? The gateway is the mole! But before we get to the
More informationChemical Quantities: The Mole Chapter 7 Assignment & Problem Set
Chemical Quantities: The Mole Name WarmUps (Show your work for credit) Date 1. Date 2. Date 3. Date 4. Date 5. Date 6. Date 7. Date 8. Chemical Quantities: The Mole 2 Study Guide: Things You Must Know
More informationCh. 10 Stoichiometry. Stoichiometry relates molar ratios between reactants and products in a chemical equation
Ch. 10 Stoichiometry Stoichiometry relates molar ratios between reactants and products in a chemical equation Used to determine moles of reactants needed Used to determine moles of products formed Conservation
More informationCHEM 100 Principles Of Chemistry. Chapter 5  How Chemists Measure Atoms & Molecules
CHEM 100 Principles Of Chemistry Chapter 5  How Chemists Measure Atoms & Molecules 5.1 Weighing Objects to Count Objects When coin parking meters are emptied, the coins are not counted but weighed By
More informationPercent Composition  Formulas
Percent Composition  Formulas This program demonstrates how to find percentage composition as well as empirical and molecular formulas from that data. Please read each section carefully. You might wish
More informationChapter 6 Chemical Calculations
Chapter 6 Chemical Calculations 1 Submicroscopic Macroscopic 2 Chapter Outline 1. Formula Masses (Ch 6.1) 2. Percent Composition (supplemental material) 3. The Mole & Avogadro s Number (Ch 6.2) 4. Molar
More informationUseful only for measuring the mass of very small objects atoms and molecules!
Chapter 9 Chemical Composition (Moles) Which weighs more, 1 atom of He or 1 atom of O? Units of mass: Pound Kilogram Atomic mass unit (AMU) There are others! 1 amu = 1.66 x 1024 grams = mass of a proton
More information21 st Century Chemistry Multiple Choice Question in Topic 3 Metals Unit 11
21 st Century Chemistry Multiple Choice Question in Topic 3 Metals Unit 11 1. Consider the equation: 2Ca(s) + O 2 (g) 2CaO(s) Which of the following statements are correct? (1) Calcium and oxygen are reactants.
More informationName Date Class CHEMICAL QUANTITIES. SECTION 10.1 THE MOLE: A MEASUREMENT OF MATTER (pages 287 296)
10 CHEMICAL QUANTITIES SECTION 10.1 THE MOLE: A MEASUREMENT OF MATTER (pages 287 296) This section defines the mole and explains how the mole is used to measure matter. It also teaches you how to calculate
More informationChapter 3 Stoichiometry Mole  Mass Relationships in Chemical Systems
Chapter 3 Stoichiometry Mole  Mass Relationships in Chemical Systems 3.1 Atomic Masses 3.2 The Mole 3.3 Molar Mass 3.4 Percent Composition of Compounds 3.5 Determining the Formula of a Compound 3.6 Chemical
More informationMoles. Moles. Moles. Moles. Balancing Eqns. Balancing. Balancing Eqns. Symbols Yields or Produces. Like a recipe:
Like a recipe: Balancing Eqns Reactants Products 2H 2 (g) + O 2 (g) 2H 2 O(l) coefficients subscripts Balancing Eqns Balancing Symbols (s) (l) (aq) (g) or Yields or Produces solid liquid (pure liquid)
More informationMatter. Atomic weight, Molecular weight and Mole
Matter Atomic weight, Molecular weight and Mole Atomic Mass Unit Chemists of the nineteenth century realized that, in order to measure the mass of an atomic particle, it was useless to use the standard
More informationMolecular Formula: Example
Molecular Formula: Example A compound is found to contain 85.63% C and 14.37% H by mass. In another experiment its molar mass is found to be 56.1 g/mol. What is its molecular formula? 1 CHAPTER 3 Chemical
More informationCHEM 110: CHAPTER 3: STOICHIOMETRY: CALCULATIONS WITH CHEMICAL FORMULAS AND EQUATIONS
1 CHEM 110: CHAPTER 3: STOICHIOMETRY: CALCULATIONS WITH CHEMICAL FORMULAS AND EQUATIONS The Chemical Equation A chemical equation concisely shows the initial (reactants) and final (products) results of
More informationChapter 3 Calculation with Chemical Formulas and Equations
Chapter 3 Calculation with Chemical Formulas and Equations Practical Applications of Chemistry Determining chemical formula of a substance Predicting the amount of substances consumed during a reaction
More information4. Aluminum chloride is 20.2% aluminum by mass. Calculate the mass of aluminum in a 35.0 gram sample of aluminum chloride.
1. Calculate the molecular mass of table sugar sucrose (C 12 H 22 O 11 ). A. 342.30 amu C. 320.05 amu B. 160.03 amu D. 171.15 amu 2. How many oxygen atoms are in 34.5 g of NaNO 3? A. 2.34 10 23 atoms C.
More informationAtomic Masses. Chapter 3. Stoichiometry. Chemical Stoichiometry. Mass and Moles of a Substance. Average Atomic Mass
Atomic Masses Chapter 3 Stoichiometry 1 atomic mass unit (amu) = 1/12 of the mass of a 12 C atom so one 12 C atom has a mass of 12 amu (exact number). From mass spectrometry: 13 C/ 12 C = 1.0836129 amu
More informationChem 115 POGIL Worksheet  Week 4 Moles & Stoichiometry Answers
Key Questions & Exercises Chem 115 POGIL Worksheet  Week 4 Moles & Stoichiometry Answers 1. The atomic weight of carbon is 12.0107 u, so a mole of carbon has a mass of 12.0107 g. Why doesn t a mole of
More information