Question

For which reaction is the enthalpy equal to `DeltaH_"f"^@` of `NO(g)`?

For which reaction is the enthalpy equal to `DeltaH_"f"^@` of `NO(g)`?

`A.` `NO(g) rarr 1/2N_2(g) + 1/2O_2(g)`
`B.` `N(g)+ O_2(g)rarr 2NO(g)`
`C.` `1/2N(g) +1/2O_2(g)rarr NO(g)`
`D.` `N_2O(g)rarr N_2(g)+1/2O_2(g)`

Answer 1

A very poor question....even by the standards of most multiple choice questions.....I would plump for `C`.......

Explanation:

The choice is between `C` and `D`. Dinitrogen gas is moderately reactive; much less reactive than dioxygen. Nevertheless, dinitrogen can be oxidized.....

`1/2N_2(g) + 1/2O_2(g)stackrel(hnu)rarrNO`

And it can also be reduced.......

`1/2N_2(g) + 3Li(s) rarr Li_3N`

I would be interested in the answer given by your lecturer. This one would stump most professors, and it should not be asked of an undergraduate.