Answer: 0.051kg
Explanation:
Using the law of calorimetry which states that the amount of heat lost by a hot substance is equal to the amount of heat gained by the cold substance.
Applying the law to this question,
Amount of heat lost by the heater = heat gained by the water
Heat lost by Immersion heater Q1 = Power×time
Given power = 500W time = 2minutes = 120seconds
Heat loss by immersion heater = 500×120 = 60,000Joules
Heat gained by water = mc∆t where;
m is the mass of the water in the bowl = ?
c is the specific heat capacity = 4.2x10³JK-1 Kg-1
∆t = change in temperature = 90°C -85°C = 5°C
= 273+5 = 278K
Substituting in the formula we have;
Q2= 4.2×10³×278×m = 1,167,600m
According to the law if calorimetry,
Q2=Q1
1,167,600m = 60000
m = 60000/1,167,600
m = 0.051kg
Therefore the mass of water in the bowl is 0.051kg
