Calculate the mass of oxygen dissolved at room temperature in $85\mathrm{.}0$ L

of the water contained within a home aquarium. Assume a total pressure of $1\mathrm{.}0$ bar

and a mole fraction for oxygen of $0\mathrm{.}22.($kH$=1\mathrm{.}3\backslash$times $103$molL$1$bar$1)$