Consider the following equation: CO + 2 H2 → CH3OH △H rxn = -128 kJ

Calculate the amount of heat (in kJ) associated with complete reaction of 8.08 g H2

To calculate the amount of heat associated with the complete reaction of 8.08 g of H2, we need to use the given information and apply the concept of stoichiometry.

First, we need to determine the number of moles of H2 present in 8.08 g. The molar mass of H2 is approximately 2 g/mol since hydrogen has an atomic mass of 1 g/mol.

Number of moles of H2 = Mass of H2 / Molar mass of H2
= 8.08 g / 2 g/mol
= 4.04 mol H2

Now we can use the stoichiometric coefficients from the balanced equation to determine the number of moles of CH3OH produced. According to the balanced equation, 2 moles of H2 react to produce 1 mole of CH3OH.

Therefore, the number of moles of CH3OH = (4.04 mol H2) / (2 mol H2/1 mol CH3OH) = 2.02 mol CH3OH

Next, we can calculate the amount of heat associated with the reaction using the given value of △H rxn = -128 kJ. Since △H rxn refers to the heat produced per mole of reaction, we will multiply it by the number of moles of CH3OH.

Heat produced = △H rxn * Number of moles of CH3OH
= (-128 kJ/mol) * (2.02 mol CH3OH)
= -258.56 kJ

Therefore, the amount of heat associated with the complete reaction of 8.08 g of H2 is approximately -258.56 kJ. The negative sign indicates that the reaction is exothermic.