Assume that one particular atom of rhodium (Rh) has a mass of 102. Why does this number not exactly match the atomic mass of 102.91 listed on the periodic table for this element?

Which statement best describes the relationship between period and frequency of light waves? a) in wave b the period increases and the frequency decreases from wave a. b) in wave a the period increases and the frequency decreases from wave b. c) in wave b the period is shorter and the frequency is greater than in wave a. d) in wave a the period is shorter and the frequency is greater than in wave b.

Which other elements contain the same number of outer electrons as sodium

What are the similarities of physical and chemical change ?