Under standing matter and energy

Question 1

Matter

Answer 1

is a substance that occupies space.

Question 2

Chemistry

Answer 2

is the science of composition, structure, properties and reactions of matter

Question 3

Molecules

Answer 3

are the smallest particle of a substance and is composed of two or more atoms.

Question 4

Particle theory

Answer 4

All matter is made up of tiny particles
Particles have empty space between them
Particles are moving randomly at all times (even if you can’t see them!)
Particles move faster and spread apart when heat is added to them.
Particles are attracted to each other.

Question 5

Pure substances

Answer 5

are substances that contain only one kind of matter; elements and compounds are pure substances.

Question 6

Homogenous

Answer 6

means always the same; showing a single form or character in all occurrences.

Question 7

Mixtures

Answer 7

are a composition of two or more substances and are capable of being separated.

Question 8

Mechanical mixtures

Answer 8

are mixtures whose components can be seen to be heterogeneous and can be separated by mechanical means.

Question 9

Heterogeneous

Answer 9

means varied in content; composed of different parts.

Question 10

A solution

Answer 10

is a mixture where the components can be separated by mechanical means.

Question 11

An element

Answer 11

is a substance composed of atoms having an identical number of protons in each nucleus.

Question 12

Radioactive

Answer 12

substances, e.g. uranium, emit ionizing rays

radioactive waste is taken away and buried in secure caverns deep below the ground, from 500m to 1000m.

Question 13

Compound

Answer 13

is a homogeneous substance composed of two or more elements

Question 14

Solvents

Answer 14

are capable of dissolving another substance

Question 15

Solutions

Answer 15

are usually made by dissolving a solute into a solvent.

Question 16

primary treatment of sewage

Answer 16

is the first step in separating a mechanical mixture and it removes nearly half of the solids found.

Question 17

secondary sewage treatment

Answer 17

the sewage is then treated to remove any harmful biological substances

Question 18

Tertiary

Answer 18

Chemicals, including chlorine and fluorine, are applied to the sewage

Question 19

Fossil fuel

Answer 19

is a source of energy derived from the ancient remains of plants and animals.

Question 20

Non-renewable refers to what

Answer 20

material that has a finite supply on the Earth.

Question 21

greenhouse gas effect

Answer 21

act like a blanket, absorbing radiation and preventing it from escaping into outer space.

Question 22

Petroleum

Answer 22

is a chemical structure composed of hydrocarbon chains of different lengths.

Question 23

ore

Answer 23

is rock or mineral from which valuable substances such as metals can be extracted.