Consider the following rxn:
CH3OH(g) -- CO(g) + 2H2(g) (delta)H=+90.7kJ

what is the enthalpy change (delta H) when 655mg of hydrogen (H2) gas reacts completely with carbon monoxide (CO) gas to form methanol (CH3OH) gas at constant pressure ?

Question

Consider the following rxn:
CH3OH(g) --> CO(g) + 2H2(g) (delta)H=+90.7kJ

what is the enthalpy change (delta H) when 655mg of hydrogen (H2) gas reacts completely with carbon monoxide (CO) gas to form methanol (CH3OH) gas at constant pressure ?

aaronq · Answer

Convert the mass of $H_2$ to moles and divide by it's stoichiometric coefficient in the equation. Multiply the number you get by the molar enthalpy.

Please post chemistry questions in the chemistry section.

anonymous · Answer

thanks a lot i'll make sure to pot it in the chemistry section next time. One last thing.. does the sign remain positive ?

aaronq · Answer

it does not, since it's the backward reaction that is under study here.

anonymous · Answer

Thank you very much.

aaronq · Answer

no problem!