All High School Physics Resources
Example Questions
Example Question #1 : Understanding Enthalpy
Enthalpy is a measure of __________.
how easily something changes temperature
total energy of a thermodynamic system
total work done by a thermodynamic system
total energy lost in heat transfer
the conversion of energy to heat
total energy of a thermodynamic system
Enthalpy, or , is the total energy of a thermodynamic system. Similar to how mechanical energy can change during mechanical processes, involving changing distances of velocities, enthalpy will increase or decrease with changes made to the thermodynamic state of the system. It is simply a measure for a different form of energy.
Example Question #2 : Understanding Enthalpy
An ice cube melts into water. While it is melting, what is the temperature of the mixture doing?
The ice part of the mixture is colder than the water part.
It remains constant while melting.
The temperature of the mixture steadily decreases while melting.
The temperature fluctuates depending upon the point at which you measure it.
The temperature of the mixture steadily increases while melting.
It remains constant while melting.
When an object is changing forms (solid to liquid in this case), the temperature remains constant. All of the energy that would normally go towards changing the internal temperature of the object is going into the latent heat of fusion or enthalpy of fusion instead.
Example Question #1 : Understanding Entropy
Entropy is a measure of __________.
energy within the system
change in heat
disorder within the system
temperature
specific heat
disorder within the system
Entropy is the measurement of disorder within a system, or how far it is from thermal equilibrium. Remember that everything in nature tends towards an equilibrium. The further from that equilibrium something is, the more "disordered" it is when compared to nature's preferred state.