States, elements and compounds

Question 1

solid

Answer 1

state of matter that has a fixed shape and volume

Question 2

liquid

Answer 2

state of matter that has a fixed volume, but no fixed shape

Question 3

gas

Answer 3

state of matter with no fixed shape or volume

Question 4

properties

Answer 4

characteristics or features of an object or substance

Question 5

diffusion

Answer 5

the spreading of one substance through another due to the movement of their particles

Question 6

volume

Answer 6

the amount of space taken up by an object or substance

Question 7

fluid

Answer 7

a substance that flows and has no fixed shape. Gases and liquids are fluids.

Question 8

particle model

Answer 8

a description of the moving particles that make up all matter and how they behave. The model explains the properties of solids, liquids and gases.

Question 9

expands

Answer 9

increase in size due to the movement of particles in a substance

Question 10

contracts

Answer 10

shorten or become smaller in size

Question 11

alchemists

Answer 11

olden-day ‘chemist’ who mixed chemicals and tried to change ordinary metals into gold. Alchemists also tried to tell the future.

Question 12

investigations

Answer 12

activity aimed at finding information

Question 13

observations

Answer 13

information obtained by the use of our senses or measuring instruments

Question 14

scientists

Answer 14

people skilled in or working in the fields of science; scientists use experiments to find out about the material world around them

Question 15

elements

Answer 15

pure substance made up of only one type of atom

Question 16

atoms

Answer 16

a very small particle that makes up all things. Atoms have the same properties as the objects they make up.

Question 17

atomic number

Answer 17

number of protons in the nucleus of an atom. The atomic number determines which element an atom is.

Question 18

chemical symbol

Answer 18

the standard way that scientists write the names of the elements, using either a capital letter or a capital followed by a lowercase letter. For example, carbon is C and copper is Cu.

Question 19

metals

Answer 19

elements that conduct heat and electricity; shiny solids that can be made into thin wires and sheets that bend easily. Mercury is the only liquid metal.

Question 20

non-metals

Answer 20

elements that do not conduct electricity or heat. They melt and turn into gases easily and are brittle and often coloured.

Question 21

metalloids

Answer 21

elements that have the appearance of metals but not all the other properties of metals