A quantity of hot water at 100oC is added to 400g of water at 10oC until the temperature of the mixture is 60oC.
Calculate the mass of the hot water added. [Specific heat capacity of water =4200JKg-1 K-1]
Calculate the mass of the hot water added. [Specific heat capacity of water =4200JKg-1 K-1]
-
A.
200g -
B.
320g -
C.
400g -
D.
500g
Correct Answer: Option D
Explanation
Heat lost by hot water = Heat gained by cold water
M x 4200 x (100 – 60 = 0.4 x 4200 x (60 – 10)
4200m x 40 = 0.4 x 4200 x 50
40m = 0.4 x 50
m = (frac{0.4 times 50}{40}) = 0.5kg
= 500g