Warm is less heaver then cold air so warm air rise and cold air sinks
1. true
2. false
3. false
4. true
5.false
6. It's true but can be false because a change in state can be a physical change as well.
Actual volume=Final Volume-initial volume

Now



If you look on Quizlet it will help you but to save you the hassle the answer is Iron.
The Law states that the change in internal energy (U) of the system is equal to the sum of the heat supplied to the system (q) and the work done ON the system (W)
<span>ΔU = q + W </span>
<span>For the first question, 0.653kJ of heat energy is removed from the system (balloon) while 386J of work is done ON the balloon, thus </span>
<span>ΔU = -653J + 386J </span>
<span>=-267J </span>
<span>Thus internal energy decrease by 267J </span>
<span>For the second question, 322J of heat energy is added to the system (gold bar) while no work is done on the gold bar, this is an isochoric/isovolumetric process, thus </span>
<span>ΔU = 322J + 0 </span>
<span>=322J </span>
<span>Thus internal energy increase by 322J</span>