# Problem: How much energy is released when 42.5 g of water freezes?

###### FREE Expert Solution
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###### FREE Expert Solution

We’re being asked to calculate the amount of energy released by freezing 42.5 g of water.

Recall that during a phase transition, the temperature is constant

Also note that freezing is an exothermic process, which means q is negative (–).

The amount of energy (q) needed to freeze a given mass is calculated using:

$\overline{){\mathbf{q}}{\mathbf{=}}{\mathbf{m}}{\mathbf{×}}{{\mathbf{\Delta H}}}_{{\mathbf{freezing}}}}$

where:

m = mass (in g)

ΔHfreezing = heat of freezing (in J/g)     *ΔHfreezing = – ΔHfusion

96% (302 ratings)
###### Problem Details

How much energy is released when 42.5 g of water freezes?

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Heating and Cooling Curves concept. You can view video lessons to learn Heating and Cooling Curves. Or if you need more Heating and Cooling Curves practice, you can also practice Heating and Cooling Curves practice problems.

What is the difficulty of this problem?

Our tutors rated the difficulty ofHow much energy is released when 42.5 g of water freezes? ...as medium difficulty.

How long does this problem take to solve?

Our expert Chemistry tutor, Sabrina took 3 minutes and 35 seconds to solve this problem. You can follow their steps in the video explanation above.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor de Laat's class at University of Guelph.