Question

Which of the following reaction has the positive value of standard enthalpy of reaction?

• A. C$_2$H$_5$OH(l) + 3O$_2$(g) $\rightarrow$ 2CO$_2$(g) + 3H$_2$O(l)
• B. 2SO$_2$(g) + O$_2$(g) $\rightarrow$ 2SO$_3$(g)
• C. 2NH$_3$(g) $\rightarrow$ N$_2$(g) + 3H$_2$(g)
• D. C(s) + O$_2$(g) $\rightarrow$ CO$_2$(g)
• E. CO(g) + $\frac12$O$_2$(g) $\rightarrow$ CO$_2$(g)

Hint:

Chemistry Tip: Most combustion reactions are strongly exothermic, so their $\Delta H$ is negative.

Answer 1

The Correct Option is C