AQA GCSE Combined Science Chemistry - atomic structure and the periodic table

Paper 2

What are the three subatomic particles?

Proton, neutron, and electron.

What is the charge and mass of a proton?

Charge: +1, Mass: 1

What is the charge and mass of a neutron?

Charge: 0, Mass: 1

What is the charge and mass of an electron?

Charge: -1, Mass: less than 0

Where are protons and neutrons found?

In the nucleus.

Where are electrons found?

In shells around the nucleus.

What is the atomic number?

The number of protons in an atom.

What is the mass number?

The number of protons + neutrons.

How do you calculate the number of neutrons?

Mass number − atomic number.

What are isotopes?

Atoms of the same element with different numbers of neutrons.

How are elements arranged in the modern periodic table?

By increasing atomic number.

What are groups in the periodic table?

Vertical columns; elements in the same group have similar chemical properties.

What are periods in the periodic table?

Horizontal rows; show the number of electron shells.

What are the properties of metals?

Conduct heat and electricity, malleable, shiny, high melting point.

What are the properties of non-metals?

Poor conductors, brittle, dull, lower melting point.

What are noble gases and why are they unreactive?

Group 0 elements – full outer shell of electrons.

Why do Group 1 metals become more reactive down the group?

Outer electron is further from the nucleus – more easily lost.

What happens when Group 1 metals react with water?

Produce a metal hydroxide and hydrogen gas.

What are the Group 7 elements called?

Halogens.

What happens to reactivity in Group 7 down the group?

It decreases – harder to gain an electron.

What is a displacement reaction?

A more reactive halogen displaces a less reactive one from a solution.

Where are transition metals found

between groups 2 and 3

What are the properties of transition metals?

Good conductors, high density, form coloured compounds, variable oxidation states.

What is a compound?

Two or more elements chemically bonded.

What is a mixture?

Two or more substances not chemically bonded – can be separated.