jac words

Question 1

alchemists

Answer 1

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

Question 2

investigations

Answer 2

activity aimed at finding information

Question 3

observations

Answer 3

information obtained by the use of our senses or measuring instruments

Question 4

scientists

Answer 4

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

Question 5

elements

Answer 5

pure substance made up of only one type of atom

Question 6

atoms

Answer 6

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

Question 7

atomic number

Answer 7

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

Question 8

chemical symbol

Answer 8

he 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 9

compounds

Answer 9

substance made up of two or more different types of atoms that have been joined (bonded) together

Question 10

bonded

Answer 10

force that holds particles of matter, such as atoms, together

Question 11

mixtures

Answer 11

a combination of substances in which each keeps its own properties

Question 12

hydrogen

Answer 12

the element with the smallest atom. By itself, it is a colourless gas and combines with other elements to form a large number of substances, including water. It is the most common element in living things.

Question 13

oxygen

Answer 13

a gas in the air (and water) that animals need to breathe in; made up of particles with two oxygen atoms. Plants produce oxygen as part of photosynthesis.

Question 14

metals

Answer 14

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 15

non-metals

Answer 15

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

Question 16

metalloids

Answer 16

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

Question 17

periodic table

Answer 17

a table listing all known elements. The elements are grouped according to their properties and in order of the number of protons in their nucleus.

Question 18

group

Answer 18

in the periodic table of elements, a single vertical column of elements whith a similar nature

Question 19

inert

Answer 19

not reactive

Question 20

noble gas

Answer 20

elements in the last column of the periodic table. They are extremely inert gases.

Question 21

solid

Answer 21

state of matter that has a fixed shape and volume

Question 22

liquid

Answer 22

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

Question 23

gas

Answer 23

state of matter with no fixed shape or volume

Question 24

properties

Answer 24

characteristics or features of an object or substance

Question 25

diffusion

Answer 25

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

Question 26

mass

Answer 26

the quantity of matter in an object (usually measured in grams or kilograms)

Question 27

volume

Answer 27

the amount of space taken up by an object or substance

Question 28

melting point

Answer 28

the temperature at which a solid substance turns into a liquid (melts) or a liquid turns into a solid (freezes)

Question 29

boiling point

Answer 29

the temperature at which a liquid changes to a gas

Question 30

sublimation

Answer 30

the change in state from a solid into a gas (or from a gas into a solid) without first becoming a liquid

Question 31

precipitation

Answer 31

falling water in solid or liquid form. The type of precipitation depends mostly on the temperature in the clouds and the air around them.

Question 32

meteorologist

Answer 32

scientist who uses observation of the atmosphere to predict or explain the weather

Question 33

particle model

Answer 33

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 34

expands

Answer 34

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

Question 35

contracts

Answer 35

shorten or become smaller in size