Unit 4 - Elements, compounds & reactions 2

Question 1

A diagram or three-dimensional object that makes an idea easier to understand

Answer 1

Model

Question 2

A link between two values e.g. 2:1

Answer 2

Ratio

Question 3

The chemical symbols and numbers that show how many atoms of each element a substance contains

Answer 3

Formula

Question 4

The basic building block of an element that cannot be chemically broken down

Answer 4

Atom

Question 5

A substance made up of only one type of atom

Answer 5

Element

Question 6

Two or more atoms held together by strong chemical bonds

Answer 6

Molecule

Question 7

Two or more elements that are chemically joined together such as water (H2O)

Answer 7

Compound

Question 8

A process which changes substances by the rearrangement of their atoms

Answer 8

Reaction

Question 9

A material that is burned for the purpose of generating heat and energy

Answer 9

Fuel

Question 10

The reaction of fuels with oxygen that produces heat and energy

Answer 10

Burning

Question 11

Substance that has a ph lower than 7

Answer 11

Acid

Question 12

A substance formed from a chemical reaction

Answer 12

Product

Question 13

Reacts with an acid to neutralise it

Answer 13

Base

Question 14

A type of compound containing carbon and oxygen

Answer 14

Carbonate

Question 15

A food group containing starches and sugars

Answer 15

Carbohydrate

Question 16

A compound that contains carbon

Answer 16

Organic compound

Question 17

A large molecule made up of a very long chain of smaller molecules

Answer 17

Polymer

Question 18

When a substance reacts with oxygen and increases the amount of oxygen in a compound

Answer 18

Oxidation

Question 19

Unlikely to break up

Answer 19

Stable

Question 20

When one substance is changed into at least two new substance due to heating

Answer 20

Thermal decomposition

Question 21

Starting substances in a chemical reaction

Answer 21

Reactants