Calculate the amount of Joules needed to warm water from 21 Celsius to 66 celsius to make a cup of hot cocoa. The cup holds 308 g of water.

This will require

266.9

k

J

of heat energy.

Explanation:

To calculate the energy required to raise the temperature of any given substance, here's what you require:

The mass of the material,

m

The temperature change that occurs,

Δ

T

The specific heat capacity of the material,

c

(which you can look up). This is the amount of heat required to raise 1 gram of that substance by 1°C.

Here is a source of values of c for different substances:

Once you have all that, this is the equation:

Q

=

m

×

c

×

Δ

T

(

Q

is usually used to symbolize that heat required in a case like this.)

a is the correct answer