Chemistry

Physical and Chemical Changes

Candle vs. Ice Cube

1. What do you think will happen to the candle during this experiment?

2. What do you think will happen to the ice cube during this experiment?

3. Will the candle weigh more, less, or the same after the experiment?

4. Will the ice cube weigh more, less, or the same after the experiment?

Physical

• Physical Property- characteristic of a substance that can be observed without changing the substance into another substance.

• Physical Change- any change that alters the form or appearance of a substance but does not make the substance change into another substance.

Chemical

• Chemical Property- characteristic of a substance that describes its ability to change into another substance.

• Chemical Reaction- a change in matter that produces one or more new substances.

Chemical vs. Physical

Chemical

• Flammability

• Energy Release

• Not Reversible

Physical

• Bending

• Crushing

• Breaking

• Cutting

Concept Map Physical

Physical Reaction

Concept Map Chemical

Chemical Reaction

The Law of Conservation of Mass

• During a chemical reaction, matter is not created nor destroyed.

• The principal of conservation of mass states that in a chemical reaction, the total mass of the reactants must equal the total mass of the product.

Law of Conservation of Mass Activity

In two to three sentences describe how the nuts and bolts activity compares to the law of conservation of mass.

Candle vs. Ice Cube Part 2

1. What changes did you observe in the candle?

2. Why did these changes occur?

3. Was this a chemical or a physical change?

4. What changes did you observe in the ice cube?

5. Why did these changes occur?

6. Was this a chemical or a physical change?

Candle vs. Ice Cube Part 3

• Does the law of conservation of mass apply to both of these experiments. Explain your answer in at least 2-3 sentences.

Balancing and Understanding Common

Chemical Equations

Common Compounds

• In the space below list as many common compounds as possible. List the compound and formula.

• Example: Compound-Water Formula- H20

Common Compounds

Compound

• Sodium Chloride

• Water

• Sugar

• Oxygen Gas

• Carbon Dioxide

• Nitrogen Gas

Formula

• NaCl

• H2O

• C6H12O6

• O2

• CO2

• N2

What is a Chemical Equation

• Chemical Equation- uses chemical formulas and other symbols instead of words to summarize a reaction.

Example:

CaCO3 CaO + CO2

Structure of an Equation

Reactant- the substance that you have at the beginning of the equation.

Product- substance that you have at the completion of the equation.

CaCO3 CaO + CO2

Symbol Formula

Structure of an Equation

• Subscript- number written below and to the right of a chemical symbol.

• Coefficient- number placed in front of a chemical formula in an equation.

CaCO3 CaO + 3CO

Subscript Coefficient

Common Compounds

List the formula for the following compounds-

• Sodium Chloride

• Water

• Sugar

• Oxygen Gas

• Carbon Dioxide

• Nitrogen Gas

Structure of an Equation

Describe the following terms:

Coefficient-

Subscript-

Chemical Symbol-

Chemical Formula-

Structure of an Equation

• Label the parts of the equation

CaCO3 CaO +3CO