# Some drag-racing vehicles burn methanol, as presented by the following equation. What the mass of methanol that burns to produce an enthalpy change of #-9.00 xx 10^4# kJ?

##### 1 Answer

Approx.

#### Explanation:

Well, one way that is often useful conceptually is to regard energy,

EQUIVALENTLY..........

(I halved the equation to make the arithmetic easier! Of course I also had to halve the energy output given my approach.)

And we want an enthalpy change of

And thus the quotient,

And since for each mole of reaction, there is