rate He = 6 x rate SF₆
Further explanation
Graham's law: the rate of effusion of a gas is inversely proportional to the square root of its molar masses or
the effusion rates of two gases = the square root of the inverse of their molar masses:
![\rm (r_1)/(r_2)=\sqrt{(M_2)/(M_1) }](https://img.qammunity.org/2021/formulas/chemistry/high-school/rtkyeeaqo1uy08888ztzq9oxzml1o0h4io.png)
or
![\rm M_1* r_1^2=M_2* r_2^2](https://img.qammunity.org/2021/formulas/chemistry/high-school/fcj81suip6i3ec6v5iz86i5y83ed834872.png)
M He = 4 g/mol
M SF₆ = 146 g/mol
![\tt (r_(He))/(r_(SF_6))=\sqrt{(146)/(4) }=6.04\approx 6\\\\r_(He)=6~r_(SF_6)](https://img.qammunity.org/2021/formulas/chemistry/college/p8ygf0qwi5083q8l30qk20tv5d64e48937.png)