If 7.90 mol of C5H12 reacts with excess O2, how many moles of CO2 will be produced by the following combustion reaction? C5H12+8O2=6H2O+5CO2

moles CO₂ produced from combustion of 7.9 mole of C₅H₁₂ = 39.5 moles CO₂

Explanation:

              C₅H₁₂      +   8O₂      =>      6H₂O      +      5CO₂

Given:   7.9moles    excess                        ? moles

From Equation, 1 mole C₅H₁₂ >  5 moles CO₂

Given            7.9 mole C₅H₁₂  >         X

Solving for 'X' using ratio and proportion ...

1mole C₅H₁₂ / 7.9mole C₅H₁₂ =  5mole CO₂ / X

=> X = 5 mole CO₂ x  7.9mole C₅H₁₂ / 1mole C₅H₁₂  =  39.5 moles CO₂

≅ 40 moles CO₂ (2 sig. figs.)

2b2t

explanation:

2b2t

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.