An electronic vacuum tube was sealed off during an experiment at a pressure of `8.2 xx 10^(-10)` atm at `27^(@)C`. The volume of the tube was `30 dm^(3)`. The number of gas molecules remaining in the tube are `:`

Options

A. `6.023 xx 10^(14)`
B. `8.2 xx 6.02 xx 10^(23)`
C. `24.6 xx 10^(6)`
D. `8.2 xx 30 xx 6.02 xx 10^(23)`

Answer

A

Explanation

Moles of gas remaining,n `= ( pV)/( RT)`
`n = ( 8 .2 xx 10^(-10)xx 30)/( 0.082 xx 300) = 1 xx 10^(-9)`
Molecules of gas
`= 1 xx 10^(-9) xx 6.02 xx 10^(23)`
`= 6.02 xx 10^(14)`