the molar heat of fusion for water is 6.01 kJ/mol. the heat capacity for water is 75 J/mol deg. Which expresssion gives the quantity of energy needed to change one mol ice at 0 degrees celsius to liquid water at 25 degrees celsius?
a.)6010/(75x25)
b.)6.01+75
c.)6010+(75+25)
d.)(6010/298)+(75x25)
e.)(6010+(75x25))/298
q1 = heat to melt ice at zero C to water at zero C.
q1 = mass ice x heat fusion.
q2 = heat to move from zero C to 25 C.
q2 = mass water x specific heat water x delta T.
q total = q1 + q2
I don't see the right answer listed. Perhaps you made a typo in answer c.
Yeah i meant to put 6010+(75x25). That would be correct right? And thank you for all your help.
Yes. That would be correct. I should get extra points for that; i.e., some for the right answer and some for catching the typo. :-)
To find the quantity of energy needed to change one mole of ice at 0 degrees Celsius to liquid water at 25 degrees Celsius, we need to consider two processes: the energy required to melt the ice (heat of fusion) and the energy required to heat the melted ice to 25 degrees Celsius (heat capacity).
The expression for the quantity of energy needed can be found by adding the energy required for these two processes.
1. First, we need to calculate the energy required to melt the ice.
The molar heat of fusion for water is given as 6.01 kJ/mol. This means that 6.01 kJ of energy is required to change one mole of ice at 0 degrees Celsius to liquid water at 0 degrees Celsius.
2. Next, we need to calculate the energy required to heat the liquid water from 0 degrees Celsius to 25 degrees Celsius.
The heat capacity for water is given as 75 J/mol deg. This means that 75 J of energy is needed to raise the temperature of one mole of water by one degree Celsius.
Since we want to raise the temperature from 0 degrees Celsius to 25 degrees Celsius, we need to multiply the heat capacity (75 J/mol deg) by the temperature change (25 deg) to find the energy required.
Now, let's consider the given options:
a.) 6010/(75x25)
b.) 6.01 + 75
c.) 6010 + (75 + 25)
d.) (6010/298) + (75x25)
e.) (6010 + (75x25))/298
To calculate the quantity of energy needed, we need to consider the energy required for both processes separately and then add them together.
a.) This expression does not consider the molar heat of fusion or the specific temperature change. It only divides 6010 by the product of 75 and 25, which is not the correct calculation.
b.) This expression only adds the molar heat of fusion (6.01) to the heat capacity (75), but it does not consider the temperature change. This is also not the correct calculation.
c.) This expression adds the molar heat of fusion (6010) to the sum of the heat capacity (75) and the temperature change (25). This is not the correct calculation.
d.) This expression attempts to calculate the energy required for the two processes correctly. It divides the molar heat of fusion (6010) by the temperature (298) and adds it to the product of the heat capacity (75) and temperature change (25). However, dividing the molar heat of fusion by the temperature is not necessary, so this is not the correct calculation.
e.) This expression correctly calculates the energy required for the two processes. It adds the molar heat of fusion (6010) to the product of the heat capacity (75) and temperature change (25), and then divides the sum by the initial temperature (298). This is the correct calculation.
Therefore, the correct expression is:
e.) (6010 + (75x25))/298.