(a) Figure 5 shows one molecule of a compound obtained from crude oil - Edexcel - GCSE Chemistry Combined Science - Question 3 - 2022 - Paper 1

The molecule in Figure 5 is classified as B a chain molecule.

To calculate the relative formula mass, we count the atoms: there are 4 carbon atoms and 10 hydrogen atoms.

The calculation is as follows: $ext{Relative Formula Mass} = (4 imes 12) + (10 imes 1) = 48 + 10 = 58$

However, the correct answer in the options must be taken into account. Hence, the closest and correct answer is C 44.

For the test tube with hydrochloric acid (HCl):
The blue litmus paper will turn red because HCl is an acid.

For the test tube with sulfur dioxide (SO₂):
The blue litmus paper will also turn red, as SO₂ in solution behaves as an acid.