Question

The maximum number of molecules is present in
A. `15L` of `H_(2)` gas at `STP`
B. `0.5g` of `H_(2)` gas
C. `10g` of `O_(2)` gas
D. `5 L` of `N_(2)` gas at `STP`

Answer 1

Correct Answer - A
(1) `15L H_(2) xx (1 mol H_(2))/(22.4L H_(2)) xx (6.022xx10^(23)H_(2))/(1 mol H_(2))` molecules
`= 4.03xx10^(23) H_(2)` molecules
(2) `0.5g H_(2) xx (1 mol H_(2))/(2g H_(2)) xx (6.022xx10^(23) H_(2) "molecules")/(1 mol H_(2))`
`= 1.51xx10^(23)` molecules
(3) `10g O_(2) xx (1 mol O_(2))/(32g O_(2)) xx (6.022xx10^(23) O_(2) "molecules")/(1 mol O_(2))`
`= 1.88xx10^(23) O_(2)` molecules
(4) `5L N_(2) xx (1 mol N_(2))/(22.4L N_(2)) xx (6.022xx10^(23) N_(2) "molecules")/(1 mol N_(2))`
`= 1.34xx10^(23) N_(2)` molecules