A system receives 500g of heat and performs 200g of work. What is the change in energy Internal to the system?

Solution:
1. According to the first law of thermodynamics, the change in internal energy (\Delta Uis given by:
\Delta U = Q - W
where:
* Q is the heat added to the system.
* W is the work done by the system.

2. Given:
* Heat added (Q= 500g (caloric units)
* Work done (W= 200g (caloric units)

3. Substitute the given values into the equation:
\Delta U = 500g - 200g

4. Calculate the change in internal energy:
\Delta U = 300g

5. The change in the internal energy of the system is 300g in caloric units.