Question

How much heat is absorbed by pouring 15 grams of 100°C liquid water on a student’s hand. The water is cooled to body temperature, 37°C. Assume that all of the heat is absorbed by the hand.

Answer 1

The formula for calculating the amount of heat is expressed as

H = mcθ

where

H is the amount of heat

m is the mass of the substance

c is the specific heat capacity of the substance

θ is the change in temperature

From the information given,

m = 15 grams = 15/1000 = 0.015

c = 4186 J/KgC

Initia temperature = 100

final temperature = 37

θ = 100 - 37 = 63

H = 0.015 x 4186 x 63

H = 3955.77

The amount of heat absorbed is 3955.77 J