Chemistry Part 2 Review

Physical & Chemical Changes

100

What is the difference between a chemical and physical change?

A physical change does not change the composition, while a chemical change does

200

Give an example of chemical change.

Rusting, Reacting, forming bubbles, etc. 

300

Give an example of a physical property.

mass, density, 5 senses, weight, etc. 

400

Which action will result in a product with new properties?

1. Shredding a worksheet        

2. Baking a cake

3. Breaking a glass bowl                    

4. Cutting wood. 

Baking a cake

500

Why is vinegar freezing a physical change, and not a chemical change?

The vinegar freezing is not changing the molecules of the vinegar, it is just changing phases, so it is a physical change.

Counting Atoms

100

How many CARBON are in Na(CO₃)₂?

2

200

How many Phosphorus are in (NH₄)₃PO₄?

1

300

2P₂O₃

How many of each element is there?

  P-4    O-6

400

(NH₄)₃PO₄

How many of each element are there?

N-3

H-12

P-1

O-4

500

What does the coefficient 2 in the following formula mean? 

2H₂0

there are 2 water molecules formed together 

Equations

100

 CH₄ + 2O₂ → CO₂ + 2H₂O

What is the coefficient for water? 

2

200

What side of an equation would you find the products? 

right

300

Which is balanced?

a. C₃H₈ + 5O₂ --> 3CO₂ + 4H₂O

b. 2C₃H₈ + 5O₂ --> 3CO₂ + 8H₂O

a. C₃H₈ + 5O₂ --> 3CO₂ + 4H₂O

400

How do balanced equations follow the Law of Conservation of Mass? 

In a balanced equation, there are the same number of each atom on both sides

500

Balance this equation.

AlBr₃ + K₂SO₄ -->  KBr +  Al₂(SO₄)₃

2AlBr₃ + 3K₂SO₄ -->  6KBr +  Al₂(SO₄)₃

Natural v. Synthetic Materials

100

Synthetic materials are made from ___________________

Natural Resources

200

What are the three types of synthetic materials?

Animal, Plant, Petroleum

300

Minerals     Plastic   Crops    Cake   Basketball   Cotton  Flag  Fossil Fuels 

Which of these are natural?

Cotton, Minerals, Fossil Fuels, Crops

400

True or false.

Animals are a renewable resource.

True

500

Explain how a natural resource that was once renewable can become non-renewable. Give an example.

various responses

Endothermic/Exothermic

100

Endothermic reactions _________ (absorb/release) energy and feel ________ (hot/cold) to touch.

Absorb;cold

200

Chemical reactions that absorb energy are called __________________. Chemical reactions that release energy are called __________________

Endothermic, Exothermic

300

CaO + H2O → Ca(OH)2 + Heat

What kind of reaction is this?

Exothermic

400

A beaker of water in sunlight becomes warm. Has a chemical reaction occurred? Explain.

various answers

500

Thinking of the Law of Conservation of Mass, if the reactants are 15 grams, how much will the products be?

the same, because matter cannot be created or destroyed.