chapter 1 – matter and change

Chapter 1 – Matter and Change

Taken from Modern Chemistry written by Davis, Metcalfe, Williams

& Castka

Chemistry is a Physical Science

– Define chemistry– List examples of the branches of chemistry– Compare and Contrast• Basic research• Applied research• Technological development

Section 1 - Objectives

Section 1-1

Chemistry is the study of the composition, structure, and properties of matter and the changes it undergoes.

What is it made of?Makeup and internal arrangement?What happens when we

heat?cool?

Mix with other materials? Why does this behavior occur?

Section 1-1 (continued)

Six main Branches of ChemistryOrganic – deals with carbon containing compounds

Inorganic – study of substances not classified as organic, mainly those that don’t contain carbon

Physical – study of properties, changes and relationship between energy and matter

Analytical – identification of components and composition of materials

Biochemistry – study of substances and processes occurring in living things

Theoretical – using math and computers to design and predict the properties of new compounds

Section 1-1 (continued)

A Chemical is any substance that has a definite composition.

Section 1-1 (continued)

The 3 often overlap – understanding of

crystals and basic light allowed lazers to be

created which lead to fiber optics

Matter and Its Properties

– Distinguish between the physical properties and chemical properties of matter.

– Classify changes of matter as physical or chemical.– Explain the . . . states in terms of particles• Gas• Liquid• Solid

– Distinguish between a mixture and a pure substance

Section 2 - Objectives

Section 1-2M & MMass is a measure of the amount of matter.

Measured in Kg, g and for the less educated ☺in lbs and ozs.

So . . .Matter is anything that has mass and takes up space.

Section 1-2 (continued)

An Atom is the smallest unit of an element that maintains the properties of that element.

and . . .an element is a pure substance made of one only kind of atom.

and . . .a compound is a substance that is made from the atoms of two or more elements that are chemically bonded.

Basic Building Blocks of Matter

Section 1-2 (continued)

An molecule is the smallest unit of an element or compound that retains the properties of that element or compound .

Basic Building Blocks of Matter (continued)

EXAMPLES

O2 H2O

Section 1-2 (continued)

Extensive properties depend on the amount of matter present

– Volume– Mass– Amount of Energy

Properties and Changes in Matter

Intensive properties do not depend on the amount of matter present

– Melting pt.– Boiling pt.– Density– Ability to conduct:– Heat– Electricity

Section 1-2 (continued)

Physical Properties and Physical Changes

Physical property is a characteristic that can be observed without changing the identity of the substance

– Melting pt.– Boiling pt.

A change in a substance that does not involve a change in the identity of the substance is called a physical change

– Grinding– Cutting

– Melting & Boiling

Section 1-2 (continued)

Physical Properties and Physical Changes (continued)

Change of state is a physical change of a substance from one state to another.

Section 1-2 (continued)

Chemical Properties and Chemical Changes

A Chemical property relates to a substances ability to undergo changes that transform it into different substances.

– Ability to burn in air– Iron rusting by combining with the oxygen in air

A change in which one or more substances are converted into different substances is called a

chemical change.

Section 1-2 (continued)

Chemical Properties and Chemical Changes (continued)

Carbon plus oxygen yields (or forms) carbon-dioxide

Carbon + oxygen carbon-dioxide

C + O2 CO2

The substances that react in a chemical change are called the reactants.

The substances that are formed in a chemical change are called the products.

Section 1-2 (continued)

Chemical Properties and Chemical Changes (continued)

Chemical changes and reactions, such as combustion and decomposition, form products whose properties differ greatly from those of the reactants.

However, chemical changes do not affect the total amount of matter present before and after a reaction. The amount of matter, and therefore the total mass, remains the same.

Section 1-2 (continued)

Energy and Changes in Matter

When physical or chemical changes occur, energy is almost always involved.

The energy can take several different forms, such as heat or light.

Although energy can be absorbed or released in a change, it is not created or destroyed. It simply assumes a different form.

Section 1-2 (continued)

Classification of Matter - Mixture A mixture is a blend of two or more kinds of matter,

each of which retains its own identity and properties.

A mixture that is uniform in composition they are said to be homogeneous

Examples salt-water solutions

A mixture that is not uniform in composition is said to be heterogeneous

Examples clay & water

Section 1-2 (continued)

Classification of Matter – Pure substances A pure substance has a fixed composition and differ

from a mixture in the following ways:

1. Every sample of a pure substance has exactly the same characteristic properties.

2. Every sample of a given pure substance has exactly the same composition.

Section 1-2 (continued)

Classification of Matter – Laboratory Chemicals and PurityChemicals in laboratories are generally treated as if

they are pure. However all chemicals have some impurities.

Purity ranking depends on the needs of the users.

Elements

– Use a periodic table to name elements, given their symbols.

– Use a periodic table to write the symbols of elements given their names.

– Describe the arrangement of the periodic table.– List the characteristics that distinguish metals,

nonmetals, and metaloids.

Section 3 - Objectives

Section 1-3 Introduction to the Periodic Table

The vertical columns of the periodic table are called groups.

The horizontal rows of elements in the periodic table are called periods.

Section 1-3 (continued)

Introduction to the Periodic Table (continued)

HydrogenHeliumOxygenCarbonNeonIron

NitrogenSilicon

Magnesium

Sulfur

Ten most common elements in the Milky Way Galaxy

Oxygen

Carbon

Hydrogen

Nitrogen

Calcium

Phosphorus

Potassium

Sulfur

Chlorine

Sodium

Magnesium

Iron

Cobalt

Copper

Zinc

Iodine

Selenium

Seventeen most common elements in the Human Body

Oxygen

Silicon

Aluminum

Iron

Calcium

Sodium

Magnesium

Potassium

Titanium

Hydrogen

Ten most common elements in the Earth’s Crust

Section 1-3

Types of Elements - Metals

An element that is a good conductor of heat and electricity is a metal.

Most metals are malleable – they can be hammered or rolled into thin sheetsThey are also ductile which means they can be drawn in to fine wire. Metals that behave this way have a high tensile strength.

The periodic table is divided into two main groups – metals and non-metals. Metals to the left and non-metals to the right.

Section 1-3

Types of Elements - Nonmetals

A nonmetal is an element that is a poor conductor of heat and electricity.

Many nonmetals are gas at room temperature , when solid they tend to be brittle.

Section 1-3 Types of Elements - metalloids

A metalloid is an element that has some characteristics of

metals and some characteristics of nonmetals.

Metalloids tend to be semiconductors.

Section 1-3 Types of Elements – Noble Gases

The elements in group 18 of the periodic table are generally unreactive.

Chapter Summary Questions

HW – page 261 ,5-13 ,17 ,19 , 20 & 23

Chapter Summary Questions

1 - Chemistry is the study of the compostion, structure and properties of substances and the changes they under go

5

a) A measure of the amount of matter

b) the amount of space occupied by matter

6

The portions of elements in a pure substance are fixed.

7

a) A property is any characteristic of a substance or material.

b) Properties can be compared in order to classify unknown materials as members of known groups or subgroups of substances, or to identify substances directly.

8

Extensive properties depend on the amount of matter that is present. Intensive properties do not.

9

a. a characteristic that can be observed or measured without changing the identity of the substance.

b. Examples include color, odor, length, size , melting point & boiling point.

10

a. a property that describes the ability of a substance to undergo changes that alter its identity.

b. Examples include the ability of coal to burn and the ability of iron (Fe) to rust.

11

A physical change is a change in a substance that does not involve a change in its identity. A chemical change is a change in which a substance is converted into other substances.

12

a. solids, liquids & gasesb. A solid has a definite shape and fixed

volume , whereas a liquid has a fixed volume but takes the shape of the vessel it is in.

c. A gas has neither fixed volume or definite shape.

d. Liquids and gases take the shape of the container they are in.

13

A change of a substance from one state of matter to another.

17

The reactants are potassium (K) and water (H2O) and the products are potassium hydroxide (KOH) and hydrogen (H2)

19

a. physical , wood still woodb. chemical , composition change think tastec. physical, butter still butter

20

a. potassium (K) metalb. Silver (Ag) metalc. Silicon (Si) metalloidd. sodium (Na) metale. Mercury (Hg) metalf. helium (He) noble gas

23

a. Group 14, period 2b. Group 18, period 3c. Group 6, period 4d. Group 2, period 6e. Group 17, period 5f. Group 11, period 6