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BartSMP [9]
3 years ago
7

N2 (g) + 2O2(g) = 2NO2 (g) ΔH = 66.4 kJ 2NO (g) + O2 (g) = 2NO2 (g) ΔH = -114.2 kJ the enthalpy of the reaction of the nitrogen

to produce nitric oxide N2 (g) + O2 (g) = 2NO (g) is __________ kJ.
Chemistry
2 answers:
OLga [1]3 years ago
8 0

Answer:

Explanation:

Equation of reactions:

1. N2 (g) + 2O2(g) --> 2NO2 (g)

ΔH = 66.4 kJ

2. 2NO (g) + O2 (g) --> 2NO2 (g)

ΔH = -114.2 kJ

Final equation

N2 (g) + O2 (g) --> 2NO (g)

Inverting equation 2, note that the ΔH will now be positive.

3. 2NO2 (g) --> 2NO (g) + O2 (g)

ΔH = 114.2 kJ

Adding equation 1 and 3 together as well as their enthalpies,

N2 (g) + 2O2(g) --> 2NO2 (g)

2NO2 (g) --> 2NO (g) + O2 (g)

---------------------------------------

N2 (g) + O2 (g) = 2NO (g)

ΔH = 114.2 kJ + 66.4 kJ

= 180.6 kJ

N2 (g) + O2 (g) --> 2NO (g)

ΔH = 180.6 kJ

RSB [31]3 years ago
3 0

Answer:

ΔH  = 180.6 kJ

Explanation:

Given that:

N2 (g) + 2O2(g) = 2NO2 (g)           ΔH = 66.4 kJ

<u>2NO (g) + O2 (g) = 2NO2 (g)         ΔH = -114.2 kJ                     </u>

N2 (g) + O2 (g) = 2NO (g)              ΔH  = ????

The subtraction of both equations would yield the unknown ΔH , therefore:

ΔH = 66.4 - ( - 114.2 kJ)

ΔH  = 180.6 kJ

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