Which of the following statements describes the elements within a row of the periodic table? A. They are in the same family.
B. They have the same or nearly the same properties.
C. They have the same average atomic mass.
D. They have properties that change in a pattern.

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.