Astudent 600 ml cup of cocoa gets cold. it was only 25°c. he put it in the microwave. how many calories must transfer to the cocoa to bring it up to 70°c

To get the answer, you must know first the formula for heat.

Heat = mass X specific heat X change in temp 

We know that the mass is 600

Specific heat is 1

And the change in temperature is 70 – 25 which is 45.

Now plugging in those values:

Heat = 600 x 1 x 45 = 27,000 calories

Note: calorie is a unit of heat

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.