Calculate the temperature change in the water upon the complete melting of the ice.

Question

An 8.2-gg ice cube is placed into 265 g of water. Calculate the temperature change in the water upon the complete melting of the ice. Assume that all of the energy required to melt the ice comes from the water and that the ice cube has a temperature of 0 ∘C .

Answer 1

Heat lost by water must equal heat gained by the ice.

Heat needed to melt the ice = q = m∆Hfusion (phase change, no change in temperature)

q = (8.2 g)(334 J/g) ... I looked up the ∆Hfusion and found a value of 334 J/g

q = 2739 J This is the heat needed to melt the ice. This heat must come from the water.

To find the change in temperature (∆T) of the water, we use q = mC∆T

q = heat = 2739 J

m = mass = 265 g

C = specific heat = 4.184 J/gº

∆T = change in temperature

Solving for ∆T, we have...

∆T = q / (m)(C) = 2739 J / (265 g)(4.184 J/gº)

∆T = 2.5º