Question

How much heat is released when 27.6 g P C l subscript 3 cools from 83.1 °C to 55.6 °C? (The specific heat of P C l subscript 3 is 0.874 J/g °C).

Answer 1

Answer: Thus 663 J of heat is released when 27.6 g
`PCl_3` cools from 83.1 °C to 55.6 °C

Step-by-step explanation:

The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

`Q=m* c* \Delta T`

Q = Heat released = ?

m = mass of substance = 27.6 g

C = specific heat capacity =
`0.874J/g^0C`

Initial temperature=
`T_i` =
`83.1^0C`

Final temperature =
`T_f` =
`55.6^0c`

Change in temperature ,
`\Delta T=T_f-T_i=(55.6-83.1)^0C=-27.5^0C`

Putting in the values, we get:

`Q=27.6g* 0.874J/g^0C* -27.5^0C=-663J`

As the value of q is negative, it means the heat has been released and it is 663J