Question

How much oil at 200 degrees Celsiusmust be added to 50g of the same oil at 20 degrees celsius to heat it to 70 degrees celsius

Answer 1

Heat lost at high temperature will be used to increase temperature of oil at low temperature.

Let mass be m which is to be added.

Then,

$ms(200-70)=50s(70-20)$

Solving it we will get, $m = 19.23 g$