Terminology

Question 1

Element

Answer 1

A substance made up of only one type of atom

Question 2

Compound

Answer 2

A pure substance that is made up of two or more different types of atoms chemically joined

Question 3

Isotopes

Answer 3

Atoms that have the same number of protons but a different number of neutrons

Question 4

Molecule

Answer 4

A cluster of atoms that make up an element or a compound

Question 5

Atomic number

Answer 5

The number of protons in a nucleus; the atomic number determines what type of atom it is

Question 6

Mass number

Answer 6

The number of protons and neutrons in an atom

Question 7

Periodic table

Answer 7

A list of all the known 118 elements

Question 8

Hydrochloride acid

Answer 8

HCl

Question 9

Sulfuric acid

Answer 9

H2SO4

Question 10

Ethanoic acid

Answer 10

CH3COOH

Question 11

Sodium hydroxide

Answer 11

NaOH

Question 12

Reactants

Answer 12

Chemicals that take part in a chemical reaction; they are written on the left hand side of the arrow

Question 13

Products

Answer 13

Chemicals produced in a chemical reaction; they are written on the right hand side of the arrow

Question 14

Word equation

Answer 14

Simple written description of what is happening in a reaction

Question 15

Acid

Answer 15

A substance that releases hydrogen ions into an aqueous solution

Question 16

Base

Answer 16

A substance that releases hydroxide ions

Question 17

Concentration

Answer 17

The amount of a substance in a defined space

Question 18

Indicator

Answer 18

A chemical that changes colour to show whether a substance is acidic, neutral or basic