Periodicity

Question 1

Atomic radius trend

Answer 1

Atomic radius decreases across period. This is because positive charge increases across a period due to the increasing proton number and this means the electrons are attracted closer to the nucleus, making the atomic radius smaller

Question 2

Element classification

Answer 2

An element is classified as s, p, d or f block according to its position in the Periodic table

Question 3

Ionisation energy trend

Answer 3

Ionisation energy generally increases across a period due to the increasing positive charge in the nucleus attracting the outer shell electrons more strongly

Question 4

Periodicity

Answer 4

Trends in element properties with increasing atomic number. The trends are caused by the changes in element atomic structure

Question 5

Proton number

Answer 5

The number of protons found in the nucleus of every atom of that element. Elements are arranged in the periodic table in order of increasing proton number.