Chemical Reactions

Question 1

What makes up a crystalline structure?

Answer 1

A repeating pattern

Question 2

Balance the following equation:

N2 + H2 -> NH3

Answer 2

N2+3H2 -> 2NH3
_________________
N=2 I N=2
H=6 I H=6

Question 3

What makes up a polymer?

Answer 3

A long repeating chain of molecules

Question 4

Explain the law of conservation of mass.

Answer 4

Mass stays the same before and after a reaction.

Question 5

What happens during an endothermic reaction?

Answer 5

Heat is absorbed

Question 6

What happens during an exothermic reaction?

Answer 6

Heat is released

Question 7

Complete the table

Physical property/Property change/Chemical property/Chemical change

Answer 7

Physical property
Does not change the identity of the substance
Ex: Color / shape / density / volume / mass / boiling point

Physical change
Form is altered by does not change the identity of the substance
Ex: Freezing / melting / dissolving / changing shape

Chemical property
Describes how substances can become new substances
Ex: ability to rust / burn / tarnish

Chemical change
Substances change into one or more different substances
Ex: Change in color / odor / temperature / rusts / burns / tarnish

Question 8

What pH would be the strongest base?
Strongest acids?
Weakest base?
Weakest acid?
Neutral?

pH
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Answer 8

Strongest Base = 15
Strongest Acid = 0
Weakest Base = 8
Weakest Acid = 6
Neutral = 7

Question 9

What color litmus paper to test?
Acid:
Base:

What color will the litmus paper turn?
Acid:
Base:

Answer 9

Color of Litmus paper to test
Acid: Blue
Base: Red

Color the litmus paper will turn?
Acid: Red
Base: Blue

Question 10

What is created when you add an acid and a base?

Answer 10

Salt and water