Question

Carbon dioxide is produced from carbon and oxygen by the exothermic reaction represented below:

$C\left(s\right)+O_2\left(g\right)\to C{O}_2\left(g\right)+394kJ$

When $2$ moles of carbon dioxide are produced by the reaction. Which of the following occurs?

• A. $197$ kilojoules are absorbed
• B. $394$ kilojoules are absorbed
• C. $788$ kilojoules are released
• D. $197$ kilojoules are released

Answer 1

The correct option is C $788$ kilojoules are released

The formation of Carbon dioxide from Carbon and Oxygen can be written as-

$C$ $+$ $O_2$ $=$ $C{O}_2$ $+$ $heat$

Formation of Carbon dioxide from Carbon and Oxygen is an exothermic reaction. Almost $394kJ$ of heat is produced or given off.

From the equation it is seen that since it is an exothermic reaction-

$1$ mole of $C{O}_2$ releases $394kJ$ of heat

Thus, $2$ mole of $C{O}_2$ releases ($394$$\times$$2$) that is $788kJ$ of heat.

Option E is the correct answer.