Using the values for the heat of fusion, specific heat of...

Using the values for the heat of fusion, specific heat of water, and/or heat of vaporization, calculate the amount of heat energy in each of the following: a. joules released when $125 \mathrm{~g}$ of steam at $100^{\circ} \mathrm{C}$ condenses and cools to liquid at $15.0^{\circ} \mathrm{C}$ b. kilocalories needed to melt a $525-\mathrm{g}$ ice sculpture at $0^{\circ} \mathrm{C}$ and to warm the liquid to $15.0^{\circ} \mathrm{C}$ c. kilojoules released when $85.0 \mathrm{~g}$ of steam condenses at $100^{\circ} \mathrm{C},$ cools, and freezes at $0^{\circ} \mathrm{C}$

Using the values for the heat of fusion, specific heat of water, and/or heat of vaporization, calculate the amount of heat energy in each of the following:
a. joules released when $125 \mathrm{~g}$ of steam at $100^{\circ} \mathrm{C}$ condenses and cools to liquid at $15.0^{\circ} \mathrm{C}$
b. kilocalories needed to melt a $525-\mathrm{g}$ ice sculpture at $0^{\circ} \mathrm{C}$ and to warm the liquid to $15.0^{\circ} \mathrm{C}$
c. kilojoules released when $85.0 \mathrm{~g}$ of steam condenses at $100^{\circ} \mathrm{C},$ cools, and freezes at $0^{\circ} \mathrm{C}$

Key Concepts

Specific Heat Capacity

Specific heat capacity is a property of a substance that indicates the amount of heat required to raise the temperature of a unit mass of the substance by one degree Celsius (or one Kelvin). It is used to calculate the energy change when the temperature of a substance changes without a phase change.

Latent Heat

Latent heat refers to the energy absorbed or released by a substance during a phase change at constant temperature. This includes the heat of fusion (energy required to change a substance from solid to liquid, or vice versa) and the heat of vaporization (energy required to transform a substance from liquid to gas, or vice versa).

Phase Transitions

Phase transitions are the processes where a substance changes from one state of matter to another, such as melting, freezing, condensation, or vaporization. During these transitions, the substance undergoes a significant energy exchange without a change in temperature, governed by latent heat.

Unit Conversion in Thermal Calculations

Unit conversion in thermal calculations involves converting between different energy units such as joules, kilojoules, and kilocalories. Understanding these conversions is crucial for properly expressing energy results in various measurement systems and ensuring consistency in calculations.

Transcript

00:01 Let's calculate the heat amount of energy required for the first one in joules and the amount of energy released when 125 grams of steam so you have for the first one you have water its gas will condense to condenses to water it will condense to liquid water right, it's still at 100.

00:31 This is still at 100 degrees celsius and this would then cool like this is going cool to 15 didn't cool to 15 degree celsius means you have water so the heat here in the first stage is the latent heat and that's just the heat of the heat of the polarization right the heat of the polarization times the mass of water well at this point it is mass of water times the specific capacity of water times the change in temperature so the total heat would be that the heat of the polarization times the mass of water plus mass of water times specific capacity of water times the change in temperature into the heat of the polarization in joules 2330 times 125 plus 2230 sorry 125 multiplied by 4 .18 times 100 minus 15 at the end of the day in joules this will give you 323 thousand one hundred and sixty two point five joules the green part now you have in kilocalories you have ice so we have water solid will melt at zero degrees melts to water liquid and then this is warmed to water liquid at a different temperature so of course this was a zero this is at 15 this was then warmed right so again, the heat here that the heat is latent heat you know heat that does not involve any change in temperature percurses changes in state so that would be the heat of fusion of ice times the mass of ice plus here the mass of water times the specific capacity of water times the change in temperature so the q to follow this but we want this in kilocalories so i'm going to be using their values in kilocalories the heat of fusion is in kilocalories is 80 multiplied by 52 .5 plus 52 .5 times the specific capacity of water in skin calories is 1 per gram times the change in temperature is 15 minus 0 .15...

Please give Ace some feedback