1. First, you want to convert cal to Joules (cal --> J).
To do this, multiply the value of cal by 4.184 (1 cal = 4.184J)
500cal x 4.184J = 2092J
------------ 1 cal
2. Calculate the change in internal energy of the gas (ΔU = heat – work).
ΔU = 2092J heat - 500J work
= 1595J change in internal energy
ΔEint=Q-W
So, ΔEint=150J
W=250J
Solve for Q.
Q= 400J
internal energy change in words is the difference between the added energy and the original energy 100 - 60 = 40J
Both the stirring and the heat energy added will increase the internal energy, so all you need to do is add both together. Don't forget to convert the calories to joules first.
When heat is added to or is absorbed by a system, its internal energy increases. The amount of external work a system can do essentially refers to the amount of energy it can transfer to something else. So when internal energy increases, so does the external work done by the system.
Physical Change
The change would be 100 joules, because an isochoric system can not perform the work.
internal energy change in words is the difference between the added energy and the original energy 100 - 60 = 40J
Basically what it comes down to is the substance that is left behind during the phase change (say the liquid when it is changing to a vapor) has a lower internal energy than it had before the phase change started. To maintain the substance at its original temperature, an equivalent amount of energy must be added to make up for the loss of internal energy due to the phase change. (Conservation of Energy)The energy added in this case is heat, which in turn causes more molecules of the substance to change phases and lowers the internal energy & the process repeats. This is why the temperature remains constant as you add heat to a substance during a phase change. Once the phase change is completed the added heat will eventually cause the temperature to rise in the new phase of the substance. Hope this explanation helps. It's kind of hard to explain without a basic knowledge of thermodynamics.
The added energy is used in the phase change to break intermolecular bonds.It is used for the phase change. ~ APEX
Both the stirring and the heat energy added will increase the internal energy, so all you need to do is add both together. Don't forget to convert the calories to joules first.
When energy is added during a phase change the energy is used to break molecular bonds.
When heat is added to or is absorbed by a system, its internal energy increases. The amount of external work a system can do essentially refers to the amount of energy it can transfer to something else. So when internal energy increases, so does the external work done by the system.
Heat energy must be added to or subtracted from a substance to cause a phase change.
The added energy is used in the phase change to break intermolecular bonds.It is used for the phase change. ~ APEX
The internal energy of air can be increased by adding heat to it. When heat is added to air, the energy of the air molecules increases, causing them to move faster and have higher kinetic energy. This increase in kinetic energy results in an increase in the internal energy of the air.
Physical
Physical Change
When energy is added during a phase change the energy is used to break molecular bonds.