Two glass bulbs A and B are connected by a very small tube having a stop cock. Bulb A has a volume of 100 `cm^(3)` and contained the gas, while bulb B was empty. On opening th stop cock. The pressure fell down to 40%. The volume of the bulb B must be:

Options

A. 75
B. 150
C. 125
D. 200

Answer

B

Explanation

According to Boyle’s law,
`P_A xx V_A = 0.4P_A xx V_B`
or `100 xx P_A = 0.4 P_A xx V_B or, V_B = 250 `cc.
Before opening the stopcock, volume of gas in bulb B must be (250 - 100) = 150mL.