Aquantity of an ideal gas is collected in a graduated tube over the mercury in a barometer type arrangement. the volume of gas at 20°c is 50ml and the level of mercury is 100mm above the outside of the mercury level. the atmospheric pressure is 750mm. the volume of gas at stp is

Answer : The volume of gas at STP is 6.21 mL

Explanation :

Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.

The combined gas equation is,

where,

= initial pressure of gas = 100 mmHg

= final pressure of gas = 750 mmHg

= initial volume of gas = 50 mL

= final volume of gas = ?

= initial temperature of gas =

= final temperature of gas at STP =

Now put all the given values in the above equation, we get:

Therefore, the volume of gas at STP is 6.21 mL