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a bag containing 0 oc ice is much more effective in absorbing energy than one containing the same amount of 0 oc water. (a) how much heat transfer is necessary to raise the temperature of 0.800 kg of water from 0 oc to 30.0 oc? (b) how much heat transfer is required to first melt 0.800 kg of 0 oc ice and then raise its temperature?

User Youurayy
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Final answer:

To raise the temperature of 0.800 kg of water from 0°C to 30.0°C, 100.32 kJ of heat transfer is required. To melt 0.800 kg of ice and then raise its temperature, a total of 367.52 kJ is needed. This illustrates that ice absorbs more energy due to the heat of fusion.

Step-by-step explanation:

Heat Transfer Calculation for Water and Ice

To answer question (a) regarding how much heat transfer is necessary to raise the temperature of 0.800 kg of water from 0°C to 30.0°C, we use the specific heat capacity formula: Q = mcΔT.

Here, Q is the heat transfer, m is the mass, c is the specific heat capacity of water, which is approximately 4.18 kJ/kg°C, and ΔT is the change in temperature.

Plugging in the values, we get:

Q = (0.800 kg)(4.18 kJ/kg°C)(30.0°C - 0°C)

= 100.32 kJ

For question (b) about how much heat transfer is required to first melt 0.800 kg of 0°C ice and then raise its temperature, we have to consider the heat of fusion.

The heat of fusion for water is about 334 kJ/kg.

So, the heat needed to melt the ice is:

Qₘ = (0.800 kg)(334 kJ/kg)

= 267.2 kJ

After the ice has melted into water at 0°C, we can use the previous specific heat capacity formula to calculate the energy required to raise the temperature to 30.0°C:

Qₙ = (0.800 kg)(4.18 kJ/kg°C)(30.0°C) = 100.32 kJ

Adding both the heat of fusion and the heat capacity gives us the total heat transfer for melting and heating the ice:

Total Heat Transfer = Qₘ + Qₙ = 267.2 kJ + 100.32 kJ

= 367.52 kJ

This substantial difference in energy required to bring ice to the same final temperature as water demonstrates that the ice is indeed more effective in absorbing energy.

User David Skrundz
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