How Do You Calculate Energy Changes in Water Phase Transitions?

AI Thread Summary
To calculate energy changes during water phase transitions, specific heat capacities and latent heat values are essential. For the first problem, the total energy released when 10g of steam condenses and cools to water at 0 degrees C involves summing the energy from condensation and cooling. In the second problem, 1840 calories of heat added to 300g of ice will determine how much ice melts based on the latent heat of fusion. The third scenario requires calculating the final state of water after removing 3600 calories from 5g of steam, indicating whether it remains as steam or condenses. Lastly, the temperature of the remaining water after rapid evaporation can be assessed by considering the cooling effect of evaporation on the mass of water left.
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Homework Statement



1. What amount of energy is released whan 10g of steam at 100 degrees C condenses and then cools to water at 0 degrees C?

2. 1840 calories of heat is added to a 300g block of ice at 0 degrees C. what amount of ice melts?

3. 3600 calories of heat is removed from 5g of steam initially at 100 degrees C. In what form is the water in the end?

4. Consider 35g of water at 1000C. If 4g rapdily evaporates, what will be the temperature of the remaining 31 grams of water?

Homework Equations



Q = mcT

The Attempt at a Solution



1. it takes 540 then 100 then 80...do i add those up and multiply by 10?
2. no idea
3. no idea
4. i know evaporation is a cooling process so there will be less heat in the 31 grams of water...but nothing else
 
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Use the relation between heat capacity, mass, temperature and heat.
Look up values for heat capacity, specific heat capacity and latent heat of fusion/melting for water.
 
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