Question

if the heat of combustion for a specific compound is -1070.0 kj/mol and its molar mass is 68.85 g/mol, how many grams of this compound must you burn to release 710.50 kj of heat? mass:

Explanation:

Step1: Calculate the moles of the compound

We know that the heat of combustion is \( - 1070.0\space kJ/mol\). To find the number of moles \(n\) needed to release \(Q = 710.50\space kJ\) of heat, we use the formula \(n=\frac{Q}{\vert\Delta H_{comb}\vert}\).

$$n=\frac{710.50\space kJ}{1070.0\space kJ/mol}$$

$$n = 0.664\space mol$$

Step2: Calculate the mass of the compound

We know that the molar mass \(M = 68.85\space g/mol\) and the number of moles \(n=0.664\space mol\). Using the formula \(m = n\times M\)

$$m=0.664\space mol\times68.85\space g/mol$$

$$m = 45.7\space g$$

Answer:

\(45.7\space g\)