# If the pressure is 0.7*atm, what length of mercury column will this pressure support?

Approx. $532 \cdot m m \cdot H g \ldots \ldots \ldots .$
$\text{One atmosphere}$ will support a column of mercury that is $760 \cdot m m \cdot H g$..........And thus a column of mercury is a good visual measure of the pressure of a quantity of gas.......
And so 0.7*cancel(atm)xx760*mm*Hg*cancel(atm^-1)=??*mm*Hg.