A spherical balloon of 21 cm diameter is to be filled with H2 at STP from a cylinder containing the gas at 20 atm at 270C. The cylinder can hold 2.82 L of water at STP. The number of balloon that can be filled

Volume of balloon =     43πr3 =43×227×(212)3 =4851mlVolume of cylinder=2820 ml’Volume of H2 at STP=20×2820×273300×1 =51324 mlAfter filling the cylinder volume of H2  is equal to = 2820ml