What is the amount of heat required to raise the temperature of a 0.02 kg of ice cube from \(-10^oC\) to \(10^oC\) ?

[specific latent heat of fusion of ice = 3.34 x \(10^5\)  \(Jkg^-1\), Specific heat capacity of water = 4200 \(Jkg^-1\) \(k^-1\)  

Specific heat capacity of ice = 2100 \(Jkg^-1\) \(k^-1\)

A.

6680 J

B.

1680 J

C.

7520 J

D.

7940 J

Correct answer is D

Quantity of heat required to raise the temperature of the ice cube from \(-10^oC\) to \(0^oC\)
⇒H=mc►ø = 0.02 × 2100 × 0 -(-10)

⇒ H = 0.02 × 2100 × (0 + 10) = 0.02 × 2100 × 10

⇒ H = 420 J

quantity of heat required to melt ice at \(0^oC\)

⇒ H = mL = 0.02 × 3.34 × \(10^5\)

⇒H=6680 j

Quantity of heat required to raise the temperature of the melted ice cube (water) from \(0^oC\) to \(-10^oC\)

⇒H=mc►ø = 0.02 × 4200 × (10-0)

⇒H = 0.02 × 4200 × 10

⇒H = 840j

;420 + 6680 + 840 = 7940 j