Question

At a partial temperature ,a certain quality of gas occupies a volume of 74cm3 at a pressure of 760mm.if the pressure is decreased to 740mm, what will be the volume of the gas at the same temperature

Answer 1

Answer:

We use the equation of state for the two sets of conditions: first

PV=nRT.

holds always for an ideal gas. Here P=1000 mmHg, T=(273+40)K=313 K. n and R are constant, but they turn out to be unimportant in what follows.

At standard pressure and temperature, P′=760 mmHg, and T′=273 K; we want to find V′ . We can likewise write

P′V′=nRT′.

Dividing the equations, P′PV′V=T′T

Hence 760mmHg1000mmHgV′480mL=(273+40)K273K

Solving, we have V′≈1.51×480mL=724mL

As we see, there is absolutely no need to convert to SI units — this is the power of using ratios when solving physics problems.