Question

How much heat is absorbed when 40.00 g of C( s) reacts in the presence of excess SO 2( g) to produce CS 2( 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

159.77kJ

Explanations:

Given the balanced chemical reaction between carbon C(s) and SO2(g) expressed as:

`5C\mleft(s\mright)+2SO_2\mleft(g\mright)\to CS_2\mleft(l\mright)+4CO\mleft(g\mright);\text{ }\Delta H\degree=239.9kJ`

First, we need to get the number of moles of Carbon present using the formula;

`\begin{gathered} \text{Moles =}\frac{Mass}{molar\text{ mass}} \\ \text{Moles of C=}(40.0g)/(12gmol^(-1)) \\ \text{Moles of C = }3.33\text{moles} \end{gathered}`

According to the reaction, 5 moles of carbon reacts to produce 239.9 kJ of heat.

To determine how much heat will be produced by 3.33 moles of Carbon, this will be expressed as:

`\begin{gathered} H_c=\frac{3.33\text{moles}}{5\text{moles}}*239.9kJ \\ H_c=(798.867)/(5)kJ \\ H_c=159.77kJ \end{gathered}`

Hence the amount of heat absorbed when 40.00 g of C( s) reacts in the presence of excess SO 2( g) to produce CS 2( l) and CO(g) is 159.77kJ