The optimum drinking temperature for a Shiraz is 15.0 ∘C . A certain bottle of Shiraz having a heat capacity of 3.40 kJ∘C−1 is 23.1 ∘C at room temperature. The heat of fusion of ice is 6.02 kJmol−1 and the heat capacity of ice is 2.108 Jg−1∘C−1. Assume that no heat is lost to the rest of the surroundings. What minimum mass of ice, originally at -5.0 ∘C , is required to bring the final temperature to 15.0 ∘C ?

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

2b2t

explanation:

2b2t

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