Question

how many moles of methane are produced when 25.1 moles of carbon dioxide gas react with excess hydrogen

Answer 1

The moles of methane that are produced when 25.1 moles of CO2 gas react with excess H2 is 25.1 moles

calculation

write the equation for the reaction

that is CO2 +4 H2 → CH4 +2H2O

from the equation above the mole ratio between CO2 to CH4 is 1:1 therefore the moles of CH4 is also= 25.1 moles

Answer 2

The chemical equation for this reaction is this:
CO2 + 4H2 = CH4 + 2H2O
 from the equation, the mole ration of CO2 to CH4 is ratio 1:1
and CH4 = 25.1
The mole ratio of H2 to H2O is 4:2
therefore, mole of H2 = 19.1* 4/2 = 38.2
The moles of methane produced is 38.2 moles