Question

Calculate the number of kj of heat necessary to raise the temperature of 60 g of aluminium from 35°C to 55°C. Molar heat capacity of Al is 24 J mol-1 K-1.
please solve

Answer 1

Answer : ----

➡No. of moles of Al (m) = (60g)/(27 g mol-1)

= 2.22 mol

➡Molar heat capacity (C) = 24 J mol-1 K-1.

➡Rise in temperature (∆T) = 55 – 35 = 20°C = 20 K

➡Heat evolved (q) = C x m x T

▶ = (24 ) x (2.22) x (20 K)

= 1065.6 J

= 1.067 kj

Answer 2

 

Given :

Δ T = 55°C - 35°C

= > Δ T = 20°C

Number of moles = mass / molar mass

= > n = 60 g / 27 g/moles

= > n = 2.22 moles

Q = m C Δ T

= Q = 2.22 × 24 × 20

= Q = 1065.6

= Q = 1.0656

= Q = 1.066 kJ

ANSWER :

1.066 is the required answer !