Question

When 0.187 g of benzene, C6H6, is burned in a bomb calorimeter, the surrounding water bath rises in temperature by 7.48 ∘C.

Answer 1

formula: q=msT
know: MM=78.12 g/mol C6H6

step 1: plug values into formula and solve for q
step 2: g to mol
step 3: q/mol x kJ/J
step 4: kJ/mol x mol/g
step 5: check ans

q H2O=250g x 4.179 J/goC x 7.48=7814.73 J

.187 g (mol/78.12 g)=.002394 mol

q/mol=7814.73 J/.002394 mol x(kJ/1000 J)= -3260 kJ/mol

3260 kJ/mol x(mol/78.12 g)= -41.7 kJ/g

Note: ANS is negative as this is a combustion rxn.