The enthalpy change when a strong acid is neutralized by strong base is -56.1 kj/mol. if 135 ml of 0.450 m hi at 23.15 c is mixed with 145 ml of 0.500 m naoh, also at 23.15 c, what will the maximum temperature reached by the resulting solution? [assume that there is no heat loss to the container, that the specific heat of the final solution is 4.18 j/g• c, and that the density of the final solution is that of water.]

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol