Question

Calculate the amount of heat required to heat a 3.5-kg gold bar from 21 degree C to 67 degree C.

Answer 1

Solution:- This problem is based on the equation, q = m c delta T

where q is the heat energy, m is mass in grams, c is specific heat capacity in J/(g. ⁰C) and delta T is change in temperature that is, final temperature - initial temperature.

specific heat capacity, c for gold is 0.129 J/(g. ⁰C). mass is given as 3.5 kg = 3500 g

delta T = 67 - 21 = 46 ⁰C

let's plug in the values in the formula....

q = 3500 g x 0.129 J/(g. ⁰C) x 46 ⁰C

q = 20769 J

so, the amount of heat required would be 20769 J that could also be round to 21000 J (two sig figs) and could also be written as 21 kJ.