In balancing a redox reaction using half reactions what must be true concerning the number of electrons lost in the oxidation half reaction compared to the number of electrons gained in the reduction half reaction

The size (radius) of an oxygen molecule is about 2.0 ×10−10m. make a rough estimate of the pressure at which the finite volume of the molecules should cause noticeable deviations from ideal-gas behavior at ordinary temperatures (t= 300k ). assume that deviatons would be noticeable when volume of the gas per molecule equals the volume of the molecule itself.