Astatine is below iodine in group 7 of the periodic table - Edexcel - GCSE Chemistry - Question 3 - 2016 - Paper 1

To estimate the boiling point of astatine, we observe the boiling points of iodine and bromine from the given table. The boiling point of iodine is 184 °C, and since astatine is below iodine in group 7, we can infer its boiling point will be higher than that of iodine.

Examining the trend, bromine has a boiling point of 59 °C, while iodine at 184 °C suggests a steady increase. Using this information, one could estimate the boiling point of astatine around 210 °C.