Question

8CO + 17H2 → C8H18 + 8H2O

In this chemical reaction, how many grams of H2 will react completely with 6.50 moles of CO? Express your answer to three significant figures.

___ grams of H2 will react completely.

((27.6 IS NOT THE CORRECT ANSWER!!!!!)

Answer 1

I don't know why 27.6 g is not the correct answer. I believe that it is correct.

27.6 grams of
`H_(2)`.

Step-by-step explanation:

The balanced equation tells us that 17 moles of hydrogen will react completely with 8 moles of carbon monoxide. That is a molar ratio of 17/8 moles H2/molesCO.

If we start with 6.5 moles of CO, we need:

(6.5 moles CO)*(17/8 moles H2/moles CO) = 13.8 moles of H2 (3 sig figs)

Convert 13.8 moles of H2 into grams H2 by multiplying by the molar mass iof H2 (2g/mole):

(13.8 moles H2)*(2 g H2/mole H2) = 27.6 grams of
`H_(2)`.