The initial temperature of the water in a constant-pressure calorimeter is 24°c. a reaction takes place in the calorimeter, and the temperature rises to 87°c. the calorimeter contains 367 g of water, which has a specific heat of 4.18 j/(g·°c). calculate the enthalpy change (δh) during this reaction

Answer : The enthalpy change during the reaction is 4.74 kJ/mole

Explanation :

First we have to calculate the heat released during the reaction.

where,

q = heat released = ?

= specific heat of water =

m = mass of water = 367 g

= final temperature of water =

= initial temperature of metal =

Now put all the given values in the above formula, we get:

Thus, the heat released during the reaction = 96.6 kJ

Now we have to calculate the enthalpy change during the reaction.

where,

= enthalpy change = ?

q = heat released = 96.6 kJ

n = number of moles water =

Therefore, the enthalpy change during the reaction is 4.74 kJ/mole

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

i'm pretty sure its b i might be wrong though!