A `4.0 dm^(3)` flask containing `N_(2) at 4` bar was connected to a `6.0 dm^(3)` flask containing helium at `6` bar , and the gases were allowed to mix isothermally. The total pressure of the resulting mixture will be

Options

A. `10.0 ba r`
B. `5.2 ba r`
C. `1.6 ba r`
D. `5.0 ba r`

Answer

B

Explanation

At constant temperature and for fixed moles , we can apply Boyle's law
`p_(N_(2)) V_(N_(2)) + p_(He)V_(He) = p_("total")v_("total")`
`(4 "bar") (4 dm^(3)) + (6 "bar") (6 dm^(3)) = p_("total")(10dm^(3))`
`:. P("total") = (16 "bar" dm^(3) + 36 "bar" dm^(3))/(10 dm^(3)) = (52 "bar" dm^(3))/(10 dm^(3))`
`= 5.2 "bar"`