This question is about groups in the periodic table - AQA - GCSE Chemistry - Question 5 - 2022 - Paper 1

Rubidium is more reactive than potassium because its outer shell electron is further from the nucleus, which results in less electrostatic attraction between the nucleus and the outer electron. Consequently, there is more shielding from inner shell electrons, making it easier for the outer electron to be lost. Thus, rubidium requires less energy to remove the outer electron compared to potassium.

The balanced equation for the reaction is:

The correct statement is: The noble gases have boiling points that increase going down the group.

The relative atomic mass (Ar) of neon can be calculated using the formula:

$Ar = \frac{(90.48 \times 20) + (0.27 \times 21) + (9.25 \times 22)}{100}$

Calculating this: $Ar = \frac{(1809.6) + (5.67) + (203.5)}{100} = 20.1877$

Rounded to three significant figures, the relative atomic mass of neon is 20.2.