Question

At a constant temperature a certain mass of gas occupies 7.5It when the pressure is 800 mm of Hg. Calculate the pressure at which the volume of the gas would be decreases by 35% of its initial volume.

Answer 1

THIS IS A VERY SIMPLE APPLICATION OF BOYLE LAW.
WHICH SAYS AT CONSTANT TEMPERTAURE THE PRESSURE IS INVESRLY PROPTIONAL TO VOLUME.
IE,PV=CONSANT
INITIAL PRESSURE *INITIAL VOLUME=FINAL PRESSURE * FINAL VOLUME
HERE INITIAL PRESSURE =800 MM OF HG
INITIAL VOLUME=7.5 LT
FINAL PRESSURE=?
FINAL VOLUME=A QUANTITY OBTAINED BY REDUCING THE INITIAL VOLUME BY 35%
IE 65% OF THE INITIAL VOLUME
=65/100*7.5 lt=4.875 lt
SO ACCORDING TO EQUATION FINAL PRESSURE=INITIAL PRESSURE*INITIAL VOLUME/FINAL VOLUME=800*7.5/4.875=1230.769231 MM OF HG
PS:MM OF HG IS A UNIT OF PRESSURE