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A bag containing 0°C ice is much more effective in absorbing energy than one containing the same amount of 0°C water. (a) How much heat transfer is necessary to raise the temperature of 0.800 kg of water from 0°C to 30.0°C? (b) How much heat transfer is required to first melt 0.800 kg of 0°C ice and then raise its temperature? (c) Explain how your answer supports the contention that the ice is more effective.

a) 10.8 kJ; 11.2 kJ; Ice has a higher heat capacity
b) 10.8 kJ; 33.6 kJ; Ice has a higher heat capacity
c) 15.6 kJ; 33.6 kJ; Water has a higher heat capacity
d) 15.6 kJ; 11.2 kJ; Water has a higher heat capacity

User NeliCZka
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Final answer:

The heat transfer required to raise the temperature of water from 0°C to 30.0°C is 10.8 kJ. To first melt 0.800 kg of ice and then raise its temperature, the heat transfer required is 267.2 kJ + 11.2 kJ.

Step-by-step explanation:

(a) To calculate the heat transfer required to raise the temperature of 0.800 kg of water from 0°C to 30.0°C, we can use the equation:

Q = mcΔT

where Q is the heat transfer, m is the mass of the water, c is the specific heat capacity of water, and ΔT is the change in temperature. The specific heat capacity of water is 4.184 J/g°C.

Calculating the heat transfer:

Q = (0.800 kg)(4.184 J/g°C)(30.0°C - 0°C)

Q = 10.8 kJ

(b) To first melt 0.800 kg of 0°C ice and then raise its temperature, we need to consider the heat transfer required for both processes. The heat transfer required to melt the ice can be calculated using:

Q = mL

where Q is the heat transfer, m is the mass of the ice, and L is the latent heat of fusion of ice which is 334 J/g.

Calculating the heat transfer:

Q = (0.800 kg)(334 J/g)

Q = 267.2 kJ

Then, to raise the temperature of the melted ice from 0°C to 30.0°C, we can use the same equation as in part (a):

Q = mcΔT

Calculating the heat transfer:

Q = (0.800 kg)(4.184 J/g°C)(30.0°C - 0°C)

Q = 11.2 kJ

(c) The answer supports the contention that ice is more effective in absorbing energy because it requires a higher heat transfer to first melt the ice and then raise its temperature compared to just raising the temperature of water.

User Magoo
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