Answer to Question #314896 in General Chemistry for Katie

Question

Determine the amount of heat in kj given off when 5.43x10^5 g of NO2 are produced

>2NO (g) = O2 (g) → 2NO2 (g)

>ΔH=-114.6kJ/mol

Answer 1

From the thermochemical equation, 114.6 kJ of heat is released per 2 moles of nitrogen dioxide produced.

First, let us calculate the moles of nitrogen dioxide produced. The molar mass of nitrogen dioxide is 46.01 g/mol.

molesNO2=

1.78×104 g

46.01g/mol

=386.87mol

Then, we can calculate the amount of heat (in kJ) associated.

386.87molNO2×

114.6kJ

2molNO2

=4.43×104kJ