C1

Question 1

Atom -

Answer 1

smallest particle of an element and have a nucleus containing protons and (usually) neutrons, surrounded by electrons

Question 2

Atomic number -

Answer 2

number of protons in the nucleus of an atom

Question 3

Atomic radius -

Answer 3

half the diameter of an atom

Question 4

Bond -

Answer 4

attractive force between two particles

Question 5

Bond length -

Answer 5

distance between the centres of two atoms that are chemically joined together

Question 6

Chemical symbol -

Answer 6

letter or letters used by chemists to represent an element, e.g. the symbol for mercury is Hg

Question 7

Electron -

Answer 7

subatomic particle surrounding the nucleus of an atom. It has a relative charge of -1, and a very small mass

Question 8

Element -

Answer 8

A substance that is made of only one sort of atom, cannot be broken down

Question 9

Ion -

Answer 9

charged particle formed when an atom, or group of atoms, loses or gains electrons

Question 10

Isotopes -

Answer 10

atoms with the same number of protons and electrons, but different numbers of neutrons, are isotopes of the same element

Question 11

Mass number -

Answer 11

number of protons and neutrons in a nucleus

Question 12

Molecule -

Answer 12

particle consisting of two or more non-metal atoms chemically joined together by covalent bonds

Question 13

Neutron -

Answer 13

subatomic particle found in the nucleus of an atom and has no charge and a relative mass of 1

Question 14

Nucleus -

Answer 14

positively charged central part of an atom, made up of protons and neutrons

Question 15

Plum-pudding model -

Answer 15

outdated model of the atom in which electrons are embedded in a sphere of positive charge

Question 16

Protons -

Answer 16

subatomic particle found in the nucleus of an atom. It has a relative charge of +1 and a relative mass of 1

Question 17

Shell -

Answer 17

region of space in an atom that can hold a certain number of electrons

Question 18

Subatomic particle -

Answer 18

Particles from which atoms are made, including protons, neutrons, and electrons

Question 19

Chemical change -

Answer 19

change that produces new substances

Question 20

Chemical reaction -

Answer 20

process in which substances react to form different substances

Question 21

Electrostatic forces -

Answer 21

forces of attraction or repulsion between electrically charged particles

Question 22

Matter -

Answer 22

anything that has mass

Question 23

Model -

Answer 23

description, analogy, or equation that helps you to explain the physical world

Question 24

Particle -

Answer 24

tiny piece of matter, such as an atom, ion, or molecule

Question 25

Particle model -

Answer 25

scientific idea used to explain the properties of solids, liquids, and gases

Question 26

Physical change -

Answer 26

change, such as changes in state that does not result in new substances being made

Question 27

State -

Answer 27

the form that a substance has (solid, liquid, or gas) under given conditions of temperature and pressure