Question

How much heat is absorbed when 30.00 g of C(s) reacts in the presence of excess SO2(g) to produce CS2(l) and CO(g) according to the following chemical equation?
5 C(s) + 2 SO2(g) → CS2(l) + 4 CO(g) ΔH° = +239.9 kJ

Answer 1

Answer:

120.0 kJ

Explanation:

• First we convert the given mass of C to moles:

30.00 g C ÷ 12g/mol = 2.5 mol

• The ΔH° value given by the problem, is the heat absorbed when 5 moles of C react.

So when we have half the moles of C (2.5 instead of 5.0), the heat absorbed will also be half, thus the answer is:

• 239.9 kJ / 2 = 120.0 kJ