Question

Find the mass of ice that is required to lower the temperature of 500 g of water at 50°C to water at 0°C. (Specific latent heat ofice = 336 J/g and specific heat capacity of water = 4.2 J/g°C).

Answer 1

Given:

Mass of water = 500 g

Initial temperature = 50°C

Final temperature = 0°C

Specific heat capacity of water = 4.2 J g⁻¹°C⁻¹

Specific latent heat of ice = 336 J g⁻¹

1. Heat lost by water:

Q = mcΔT

= 500 × 4.2 × (50 − 0)

= 105000 J

2. Heat absorbed by ice:

Let the mass of ice be m.

Q = mL

105000 = m × 336

m = `105000/336`

m = 312.5 g

Mass of ice required = 312.5 g