# Chemistry

posted by
**Syed** on
.

A gas is allowed to expand at constant temperature from a volume of 2.00 L to 11.20 L against an external pressure of 1.500 atm. If the gas loses 256 J of heat to the surroundings, what are the values of q, w, and ΔU? Pay careful attention to units.

-----My attempt:

q = heat

so if the gas losses 256J of heat then that makes

q=-256J

as for w

w = -p (delta V)

w = -( 1.5atm) (11.20L-2.0L)

w = -13.8atm (convert this to J)

w = -13.8atm * (8.3145 J K^-1 mol^-1)/(0.08206 L atm K^-1 mol^-1)

w= - 1398.2J?

then Delta U = q + w

delta U = -256J + (-1398.2J)

delta U = 1654J?

Is this right?