The heat required to rise the temperature of 54 ~g of aluminium from 40^ C to 60^ C in J is (molar heat capacity of aluminium in this temperature range is 24 ~J ~mol ⁻¹ ~K ⁻¹ ; atomic weight of Al is 27)

Step-by-step solution

Given, Weight of aluminium (w)=54 ~g Temperature difference ( T)=60^ -40^ =20^ C Molar heat capacity of aluminium (C_s )=24 ~J ~mol ⁻¹ ~K ⁻¹ Atomic mass of ( Al ) , i.e. (M)=27 Moles of ( Al ) , i.e. n= w M = 54 27 =2 ~mol Heat required (Q)=n C_s T =2 24 20=960 ~J Hence, option (c) is the correct answer.