a. Describe in a few sentences how the concept of chemical element resolves the philosophical issue of change versus identity in the context of chemical reactions and how this resolution is validated by the laws of definite proportions and multiple proportions.

b. Choose an example of heat in your life and describe it in full physical terms:

1. what is the significance of this heat to you?
2. what object is changing in temperature because of this heat?
3. what is this object's mass and change in temperature?
4. what is the heatin calories (the amount of heat to raise 1 g of H₂O by 1 C)?
5. what value of specific heat incaloriesper gram-degree celsius does this imply for the object changing temperature?

c. An iron cannonball of mass 5.4 kg is heated in a fire to 480 C and then plunged into a bucket holding 0.015 m³ of water at 25 C. The cannonball and the water come to a final equilibrium temperature of 42 C. What was the specific heat of the cannonball in calories per gram-degree Celsius?

d. In a few sentences, describe the phlogiston theory of heat and the series of experiments that led to its discrediting as a valid model of heat.

e. You push down on a crowbar with 150 N of force 0.48 m from the pivot point and pull down the end through 30. How much work do you do with the other end of the crowbar in newton-meters?

f. You push a box 2.0 m across a room using 250 N of force. How muchwork do you do on the box innewton-meters?