# Two gas bulbs A and B are connected by a tube having a stop cock ,Bulb A has a volume of 100 ml and contains hydrogen .After opening the gas from bulb A to the evacuated bulb B the pressure falls down to 40 percent of initial .The volume of B must be?

_{2}

Final pressure is 40 % of the initial pressure. So P

_{2}= (40 / 100) P

Volume in A = 100 mL

Let initially volume of B = V

After opening the stop cock final volume will be (100 + V) mL

According to Boyle's law

P

_{1}V

_{1}= P

_{2}V

_{2}

P X 100 = (40/100)P X (100 + V)

100 = 40 + (40 / 100) V

100 - 40 = (40 / 100) V

(60 X 100) / 40 = V

V = 150 mL

Thus, the volume of bulb B = 150 mL.

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