Unit 2 --Chemical Reactions

Question 1

Chemical Equations

Answer 1

When atoms are rearranged to form new molecules (new substances)

Question 2

Reactant

Answer 2

A material that takes part in the reaction

Question 3

Product

Answer 3

A material that is produced by a reaction

Question 4

Word Equations

Answer 4

Names used to represent an action
eg.
Sodium metal + Chlorine gas – Sodium chloride

Question 5

Skeleton equations

Answer 5

Chemical symbols are used to represent a reaction
eg.
Na + Cl^2 – NaCl

Question 6

Law of Conservation of mass

Answer 6

States that matter cannot be created or destroyed out of nothing ( the mass and number of atoms on the product side)

Question 7

Balanced Equations

Answer 7

Chemical symbols are used such that the same number and type of atoms appear on both sides of the equation

Question 8

To balance an equation…

Answer 8

Only coefficients can be added or changed

Question 9

Synthesis Reactions

Answer 9

Two or more elements or compounds combine to form ONE new substance

Question 10

Synthesis special cases

Answer 10

1. Non-metal oxide + water
   eg.
2. Metal oxide + water
   eg.

Question 11

Decomposition Reactions

Answer 11

ONE larger molecule breaks up into 2 or more smaller ones
eg

Question 12

Decomposition Special Cases

Answer 12

1. Metal hydroxide – metal oxide + water
2. Metal Carbonate – metal oxide + Carbon dioxide

Question 13

+

Answer 13

Reacts with

Question 14

–>

Answer 14

to produce

Question 15

(s)

Answer 15

Solid

Question 16

(l)

Answer 16

Liquid

Question 17

(g)

Answer 17

Gas

Question 18

(aq)

Answer 18

Aqueous solution

Question 19

Only acids can be what ?

Answer 19

Aqueous

Question 20

Chemical Reaction

Answer 20

Process in which substances interact to form one or more different substances

Question 21

Coefficient

Answer 21

Positive number that is placed in front of a chemical formula to show the number of particles

Question 22

Single Displacement

Answer 22

One element in a compound is replaced by another

A + BC –> AC + B

A metal can displace a cation (a positive ion or
polyatomic ion)

E + DF –> DE + F

Question 23

A + BC –> AC + B

Answer 23

Single displacement

Question 24

E + DF –> DE + F

Answer 24

A metal can displace a cation
(Single Displacement)

Question 25

Special Case
(Single Displacement)

Answer 25

When a metal that is more reactive than hydrogen
reacts with water, the metal hydroxide and
hydrogen gas is produced

Ca + 2 H2O  Ca(OH)2
+ H2

Question 26

Activity series

Answer 26

A ranking of the relative reactivity of metals or halogens in aqueous reactions

Question 27

Double Displacement Reaction

Answer 27

A double reaction involves the exchange of positive ions between two ionic compounds to form new ionic compounds

Question 28

EG Double Displacement Reaction

Answer 28

AX + BY –> AY + BX

Question 29

Types of Double Displacements

Answer 29

• Reaction that forms a solid
• Reaction that forms a gas
• Reaction that forms water

Question 30

Precipitate

Answer 30

An insoluble solid that is formed by a chemical reaction between two soluble compounds

Question 31

Neutralization

Answer 31

When an acid and a base are combined

Question 32

Combustion reactions

Answer 32

Complete Combustion, incomplete combustion

Question 33

Complete Combustion

Answer 33

-reacting with oxygen 02
-reacting with any compound that has Carbon, Hydrogen, and oxygen

Produces C02 and H20

Question 34

Incomplete Combustion

Answer 34

-In the absence of sufficient oxygen, carbon-containing compounds

-produces CO, C02, H2O, and C