physics problems?

Question

a chile blows up a balloon with air. the balloon will not flaot to the ceiling because
A. the balloon and the air it contains werigh more than the air displace by the balloon
b. the eright of the balloon is less than the weight of the air displaced by the balloon
c.the pressure of the air inside the balloon is greater than the atmosphereic pressure
d. the pressure of the air inside the balloon is less than the atmospheric pressure
e. the temperature of the air inside the balloon is less than the atmopheric temperature

heat flows into a gas piston and the gas performs some work on its suuroundings. the amount of work done is less than the heat added. in this situation
a. the internal energy of the gas decreased
b. the internal energy of the gas did not change
c. hte internal energy of the gas increased
d. the gas experienced a phase change
e. energy is not conserved and so it cannot happen

Answer 1

(1).
A - yes.
B - it's possible the weight of the balloon is less then the air displaced, but this is unlikely. The weight of the balloon consists of two parts - the air within and the balloon itself.
C - yes. This will help to make the balloon heaver because there will be more molecules of air.
D - No. It's the greater pressure that causes the balloon to expand.
E - ? The temperatures could go either way. There is insufficient information given here.

(2).
A - No. When the gas molecules are heated up, it's likely they will have more energy.
B - No. The gas becomes subject to change.
C - Yes.
D - It's possible, but it not clear what exactly happens to the gas.
E - No. This contradicts the law of conservation of energy.

Answer 2

The first one is A.

The second one is C, because more energy (heat) went into the gas than came out (when it did work on its surroundings).

I'm absolutely certain of both answers.

Answer 3

(a) and (c). What's a "chile"? Proofread your stuff.