Which statement matches a subatomic particle with its charge?
(1) a neutron has a negative charge.
(2) a proton has a negative charge.
(3) a neutron has no charge.
(4) a proton has no charge.

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.