Chem

Question 1

What is a chemical reaction?

Answer 1

When 2 or more molecules interact to form a new product. (burning paper or wood, as it produces a new odour)

Question 2

Difference between ionic & molecular compounds

Answer 2

Ionic: metals & nonmetals
Molecular: nonmetals & nonmetals

Question 3

Law of conversation of mass & use it to explain why we balance chemical equations

Answer 3

Mass of reactants always equals the mass of products.
We use it to ensure that mass is conserved in the reaction.

Question 4

Difference between complete & incomplete combustion reactions. What are the products of each?

Answer 4

Complete: lots of oxygen, products are CO2 & H2O

Incomplete: little oxygen, products are H2O, CO2, CO, & C

Question 5

KNOW HOW TO… (VERY IMPORTANT)

Answer 5

-find total # of atoms in a formula
-name compounds
-write formulas
-word equations
-identify reactants & products

Question 6

Difference between acids & bases (properties)

Answer 6

Acids: sour tasting, corrode metals
Bases: bitter tasting, feels slippery

Question 7

How much more basic is a substance with a pH of 11 compared to a substance with a pH of 9?

Answer 7

x 10 x 10 = 100

Question 8

What is the pH of a neutral substance? Example?

Answer 8

7, water

Question 9

What is a pH indicator? List all indicators discussed and how they are used to detect acids & bases

Answer 9

Substances that turn different colours in acids and bases
Acid Base
Red litmus paper: Red Blue
Blue litmus paper: Red Blue
Phenolphthalein: Clear Pink
Bromothymol blue: Yellow Blue

Question 10

Neutralization reaction & products & reactants

Answer 10

Type of chemical reaction in which an acid reacts with a base to form water and a salt.

Acid + base —> salt + water

Question 11

Practical uses of acids & bases in society and the environment

Answer 11

-cleaning products
-agriculture
-medicine

Question 12

Synthesis

Answer 12

Involves the combination of smaller atoms and or molecules into larger molecules.
A+B=AB

Question 13

Decomposition

Answer 13

Involves the splitting of a large molecule into elements or smaller molecules.
AB-A+B

Question 14

Single displacement

Answer 14

Involves an element and a compound as reactants one element displaces or replaces another element from a compound.
C+AB-CB+A or D+AB-AD+B

Question 15

Double displacement

Answer 15

Occur when elements in different compounds displace each other or exchange places.
AB+CD-CB+AD

Question 16

KNOW

Answer 16

H2, O2, F2, BR2, I2, N2, CL2,