A balloonist is preparing to make a trip in a helium-filled balloon. The trip begins in early morning at a temperature of 15 degrees C. By midafternoon, the temperature has increased to 30. degrees C. Assuming the pressure remains constant at 1.00atm, for each mole of helium, calculate:

Question

(a) The initial and final volumes
(b) The change in internal energy, ΔE [Hint: Helium behaves like an ideal gas, so E=3/2nRT. Be sure the units of R are consistent with those of E.]
(c) The work (w) done by the helium (in J)
(d) The heat (q) transferred (in J)
(e) ΔH for the process (in J)
(f) Explain the relationship between the answers to (d) and (e).

Answer 1

a)Pv=nRT

1mol(.0821)(288.15)/1atm=23.7L
1mol(.0821)(303.15).1atm=24.9L
b)E=3/2nRT
1mol(8.314R)(303.15-288.15)=187J

Answer 2

c) work = -p*delta v
d) q = mass x specific heat x (Tfinal-Tinitial)
e) q_p = delta H

Answer 3

oshili onda nyenwa lela