CHEMISTRY – CHAPTER 1 Matter & Energy

Objective #3 Objective: Understand energy and matter. Before: Introduction to energy and matter During: Discuss energy and its relationship to matter After: Review energy and its relationship to matter

Energy – is the ability to cause change or do work. There are several types of energy: Chemical Electrical Mechanical Sound The law of conservation of energy states that energy cannot be created or destroyed it is simply converted from one form to another.

Energy is never lost it is simply converted into a form that cannot Be recaptured for effective use. Usually heat energy. All energy can be classified into two categories:

Kinetic energy - energy of an object in motion

Potential energy – stored energy, energy at rest or due to position.

The Building Blocks of Matter An atom is the smallest unit of an element

2. An element is a pure substance made of only one kind of atom. 3. A compound is a substance that is made from the atoms of two or more elements that are chemically bonded.

4. Two or more of the same type of atoms form elements and several different types of atoms form compounds.

Properties and Changes in Matter 1. A property is a characteristic that defines or identifies a group or substance. 2. Properties are either: Extensive properties – depend on the quantity of matter present. (mass, volume, length, and amount) Intensive properties – do not depend on the amount of matter present ( melting point, boiling point, density, conductivity 3. A physical property is a characteristic that can be observed or measured without changing the identity of the substance. (ex. Melting point and boiling point) A physical change involves a change in which the identity of a substance is not altered.

5. Phase changes (changes in states) are always a physical change. Solid Liquid Gas freezing melting deposition sublimation evaporation condensation

6. A change of state is a physical change from one state of matter to another. Solid Gas

7. The four states of matter. Solids have definite shape and volume. Liquids have definite volume but no definite shape. Gases have not definite shape or volume. Liquid Gas Solid

Plasma is a high temperature physical state of matter in which atoms lose their electrons, therefore, it contains charged particles.

Carbon + Oxygen → carbon dioxide 8. A chemical property relates to a substance’s ability to undergo changes that that transform it into different substances. Ex. Flammability, reactivity, or combustibility A chemical change or chemical reaction occurs when one or more substances are converted into a different substance. 10. The substances that react are called the reactants. The substances that are produced are called the products. Carbon + Oxygen → carbon dioxide reactants products

11. The three indications of a chemical reaction The production of heat/light The production of a gas The production of a precipitate

Endothermic – energy is absorbed. 12. All physical and chemical changes involve a change of energy. These changes can be: Endothermic – energy is absorbed. Exothermic – energy is released. 13. In the sciences a positive number (+) means endothermic and a negative number (-) means exothermic. Endothermic reactions feel cold to the touch and exothermic warm or hot. Do demo bleach and sodium sulfite and ammonium nitrate and water.

Classification of Matter 1. A mixture is a blend of two or more kinds of matter, each retaining its own identity and properties.

2. A homogenous mixture is the same throughout 2. A homogenous mixture is the same throughout. A homogenous mixture is called a solution.

3. A heterogeneous mixture is not uniform throughout

4. A pure substance has a fixed composition and is a compound or element

Chapter 1 – Section 3 Elements

Objective #4 Objective: Understand elements and the periodic table Before: Introduction to the elements and the periodic table During: Discuss the elements and the periodic table After: Review the elements and the periodic table

Elements and the Periodic table 1. The periodic table is a listing of all elements by increasing atomic number.

2. The vertical columns are called groups. There are 18 groups. 3. The horizontal rows are called periods. There are 7 periods

4. The periodic table can be separated into metals, nonmetals, and metalloids.

5. Metals are shiny, malleable, ductile, and good conductors of heat and electricity. 6. Nonmetals are not shiny, malleable, ductile, or good conductors of heat and electricity. carbon iodine sulfur phosphorus