Matter and Energy. Focus: Section 5.1. Matter and Atoms. Composition and Structure of Minerals. Identifying Minerals.

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1 Atoms to Minerals Atoms to Minerals Matter and Atoms Composition and Structure of Minerals Identifying Minerals Mineral Groups Focus: Section 5.1 Matter and Energy Matter and Atoms Key Idea Ordinary matter is composed of elements that can be broken down into particles called atoms. Objectives 1)Identify the characteristics of matter 2)Compare the particles that make up atoms of elements 3)Describe the three types of chemical bonds Key Vocabulary element mass number ion atomic number compound metal isotope molecule nonmetal Everything in the universe is made up of essentially 2 things: and. matter has mass and occupies space and is the substance of which all physical objects are made four states of matter are,,, and energy is the ability to cause change or do work forms of energy include,,, and

2 Properties of Matter Mass and Weight There are two basic properties of matter: chemical and physical : properties that change the chemical nature of matter examples: release of energy, reactivity with another substance, and flammability. : properties that do not change the chemical nature of matter examples: mass, color, shape, volume, viscosity, and density. We often use the terms "mass" and "weight" interchangeably, but to a scientist they are completely different things. is the quantity of matter in an object. is the force exerted on an object by gravitational attraction. Mass is constant all over the Universe. Weight depends on location in the Universe. If you weighed 120 pounds on Earth, you would weigh 1/6 th less on the Moon because the gravitational attraction is less. Your mass remains the same in both places. Chemical & Physical Changes Classification of Matter result when a substance is transformed into a chemically different substance. The change cannot be undone. Matter can be classified as a or a. example: a water molecule combines with oxygen to form hydrogen peroxide. result when a substance changes its physical appearance, but not its composition. The change can be undone. example: water freezes to form ice, but the substance is still water. Mixture A substance composed of two or more components, each of which retains its own properties. Heterogeneous Mixture Mixture in which the substances aren't equally distributed. Example: garden salad Homogeneous Mixture Mixture in which the composition is uniform throughout. Example: air Compound A substance formed by the chemical combination of two or more elements in definite proportion. Example: table salt Pure Substance A substance with a fixed chemical composition throughout. Element A substance made up of only one kind of atom that cannot be broken down into simpler substances. Example: carbon

3 States of Matter Modern Atomic Model Matter exists in one of four physical states:,,, or. Changes of physical state occur as heat energy increases. SOLID 1.definite shape and volume 2.not easily compressible 3.does not flow easily LIQUID 1.indefinite shape and volume 2.not easily compressible 3.flows easily GAS 1.indefinite shape and volume 2.easily compressible 3.flows easily PLASMA 1.indefinite shape and volume 2.ionized gas at very high temperature 3.good conductor of electricity Atoms are composed of,, and. Most of the mass of the atom is concentrated in the of the atom. In the number of protons is equal to the number of electrons. Electrons travel in circular orbits around the nucleus and gain or lose energy as they move from one orbit to another. Ions and Isotopes Chemical Bonding An atom with a greater or lesser number of electrons than protons is called an. # protons > # electrons = # electrons > # protons = are the forces that hold atoms together in molecules due to the sharing of electrons between atoms. The electrons of an atom that participate in chemical bonding are called. occurs when two atoms share electrons. results from the attraction of oppositely charged ions. An atom of the same element with a different number of neutrons than protons is called an. forms when electrons move freely around all the positive ions.

4 Elements Reading the Periodic Table An is a substance made up of only one kind of atom that cannot be further divided by ordinary chemical or physical means. There are known elements of which occur naturally on Earth. and are among the most abundant elements in Earth s crust. Focus: Section 5.2 What Is a Mineral? Composition and Structure of Minerals Key Idea A mineral is a naturally occurring element or compound that is inorganic and crystalline in structure. Objectives 1)Identify the characteristics of minerals 2)Explain how minerals form 3)List the physical characteristics of minerals that are influenced by their crystalline structure Key Vocabulary mineral crystal silicate silicate tetrahedron cleavage A is defined as a substance that: is ; not man made or manufactured is a ; not a liquid or gas has a has is ; not living now nor in the past

5 How are Minerals Formed? What is a Crystal? Minerals are formed inorganically as a result of specific environmental conditions. These conditions include: - the cooling and solidification of magma - precipitation from water caused by evaporation, chemical reactions, and temperature changes - the rearrangement of atoms in existing minerals that are subjected to conditions of high temperature and pressure are solids that form by a regular repeated pattern of molecules connecting together. Crystals have: orderly and symmetrical definite definite external and properties Crystal Structure Focus: Section 5.3 Crystal structures are grouped into 6. Every mineral belongs to one of these crystal classes: cubic tetragonal hexagonal orthorhombic monoclinic triclinic Identifying Minerals Key Idea Minerals can be identified by chemical and physical properties that include color, luster, crystal shape, streak, cleavage, fracture, hardness, specific gravity, reaction to an acid. Objectives 1)Identify rock forming minerals by inspection using physical properties such as color, luster, and physical shape. 2)Identify rock forming minerals using simple tests that identify both physical and chemical properties such as streak, cleavage, hardness, and specific gravity. Key Vocabulary mineralogy rock forming mineral luster streak fracture specific gravity

6 Physical Properties of Minerals Color Most common minerals can be identified by inspecting or testing their. Some of the characteristics used for identifying minerals are: is directly related to one of the major elements in the mineral and can be characteristic and serve as a means of identification. Color is not a reliable indicator of type of mineral because most minerals occur in more than one color. For example, quartz comes in several colors: rose quartz clear quartz smoky quartz Streak Luster The of a mineral is the color of the powder left on a streak plate when the mineral is scraped across it. Nonmetallic minerals usually leave a white streak and metallic minerals usually leave a dark streak. A mineral s color and streak may not be the same. refers to how light is reflected from a mineral. The two main types of luster are and. Minerals with a metallic luster reflect light and have a silvery appearance. Some of the terms used for nonmetallic luster are: transparent glassy pearly dull silver greasy oily metallic -shiny

7 Hardness Cleavage of a mineral is its ability to resist scratching. Friedrich Mohs, a German mineralogist, developed a hardness scale over 100 years ago. The ranks the order of hardness of minerals and common objects from 10 (hardest) to 1 (softest). is the tendency of a mineral to cleave, or break, along flat, even surfaces. In some minerals atomic structure is weaker in one direction than in others, so the mineral will tend to break in that direction. The hardest mineral known, diamond, was assigned the number 10. Fracture Density Minerals that do not show cleavage when broken are said to fracture. is the uneven breakage of a mineral and may be described as: conchoidal uneven or irregular splintery or fibrous is a measure of how heavy something is for its size. So, something that is very heavy and small has a high density. Density is defined as an object s ; or its mass (how much matter it contains) divided by its volume (how much space it takes up). Each box has the same volume and each ball has the same mass. Which box has the higher density? Why?

8 Density and Specific Gravity Mineral Special Properties The of a mineral is the ratio of its mass to its volume expressed in grams per cubic centimeter (g/cm³). is the ratio of the density of a mineral and the density of an equal volume of water. The density of water is 1 gram/cm³. Specific gravity can also be considered as the "heaviness" of a mineral. A mineral has a density of 3.2 grams/cm³. What is its specific gravity? 3.2 grams/cm³ 1 gram/cm³ Specific Gravity = 3.2 Some minerals have unique characteristics that can be confirmed by: Slide title: Mineral Special Properties #1 glows under ultraviolet light - continues to glow after light turned off Slide title: Mineral Special Properties #2 splits light rays that pass through it fizzes when a mild HCl acid is applied acts as a magnet gives off subatomic particles No slide: taste and smell salty taste of halite or smell of sulfur Focus: Section 5.4 Mineral Classification Mineral Groups Key Idea The most common minerals in Earth s crust are silicates and carbonates. Objectives 1)Describe the properties of the most common minerals, silicates, and carbonates 2)Describe tests used to identify mineral groups Key Vocabulary carbonate oxide sulfide Minerals are classified as,, and. Silicates consist of 4 oxygen ions surrounding a silicon ion. Nonsilicates have the same atomic structure as silicates, but with atoms or ions attached to something other than a silicon ion. Native elements are composed of atoms of a single element.

9 Silicates Nonsilicates & Native Elements Minerals that are compounds formed of silicon and oxygen are called silicates or silicate minerals. More than of the minerals in Earth s crust are silicates. The basic building block of a silicate is the (SiO 4 ) consisting of 4 oxygen ions and a silicon ion together by covalent bonds. Nonsilicate minerals are classified as,,,,, and depending on their chemical composition. Nonsilicates typically display a variety of crystalline structures. Many nonsilicates and native elements have economic value for the construction trades and industry. Nonsilicates