Chemistry

Question 1

Properties of Metaloids

Answer 1

• Characteristics of both metals and non-metals

- Good semi-conductor

Question 2

Properties of Non-metals

Answer 2

• Not good conductors of heat and electricity

- High electronegativity

Question 3

What is the same number as the atomic number?

Answer 3

The number of protons and electrons

Question 4

Electrons =

Answer 4

Protons

Question 5

Name the greenhouse gases

Answer 5

Carbon dioxide, methane, water vapour and nitrous oxide

Question 6

Greenhouse effect

Answer 6

Greenhouse gases keep heat closer to the earth for longer than it normally would, by bouncing the heat off in every direction before allowing the heat to escape, making earth say warm.

Question 7

Global Warming

Answer 7

Warming of the Earth due to the human increase of emissions of carbon dioxide, methane and nitrous oxide.

Question 8

Anions

Answer 8

negatively charged particles

Question 9

Cations

Answer 9

positively charged particles

Question 10

Covalent

Answer 10

Covalent is between two non-metals eg O2, H2

Question 11

Ionic

Answer 11

Ionic is between metal and non-metal

Question 12

Properties of Metals

Answer 12

Shiny
Malleable
Ductile
Good conductors of heat and electricity

Question 13

Mass Number

Answer 13

Number of protons and neutrons in the nucleus

Question 14

Hydrochloric acid + Sodium =

Answer 14

Sodium chloride and hydrogen gas

Question 15

Hydrochloric acid + Calcium =

Answer 15

Calcium chloride and hydrogen gas

Question 16

Types of Reactions

Answer 16

Synthesis Reactions 
Decomposition Reactions 
Single Displacement Reactions 
Double Displacement Reactions 
Combustion 
Organic Reactions 
Redox

Question 17

Characteristics of Covalent Bonds

Answer 17

Physical properties that include lower melting points and electrical conductivity

Question 18

Characteristics of Ionic Bonds

Answer 18

Soluble in water.
They are compounds formed from metals and non-metals.
In a solid state they do not conduct electricity

Question 19

Alloy

Answer 19

An alloy is a metal combined with other substances, resulting in strength, hardness, durability, ductility, tensile strength and toughness.

Question 20

Examples and Characteristics of Alloys

Answer 20

Mild Steel, Hard Steel, Cast Iron, Stainless steel. Stong and good as tools.

Question 21

2,8,1

Answer 21

Sodium

Question 22

2,8,3

Answer 22

Aluminium

Question 23

Calcium Sulphate

Answer 23

CaSO4

Question 24

Copper Chloride

Answer 24

CuCl2

Question 25

Aluminum sulfate

Answer 25

Al2(SO4)3

Question 26

Aluminum oxide

Answer 26

Al2O3

Question 27

Life Cycle of a Star

Answer 27

Stellar Nebula>Star>Red Giant>Planetary Nebula>White Dwarf OR
Stellar Nebula>Massive Star>Red Super-giant>Supernova> Black Hole or Neutron Star

Question 28

Carbon Sink

Answer 28

A carbon sink is a natural or artificial reservoir that accumulates and stores some carbon-containing chemical compound for an indefinite period

Question 29

Carbon cycle

Answer 29

Carbon dioxide goes into living tissue by photosynthesis and returns to the atmosphere through respiration, the decay of dead organisms, and the burning of fossil fuels.

Question 30

Structure of the Sun

Answer 30

The sun had 4 different layers, the Photo-sphere, convective zone, radiate zone and the solar interior