What is the pressure in millimeters of mercury of 0.0135 mol of helium gas with a volume of 215 mL at a temperature of 45 ∘C?

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.

What is another way to determine mass times acceleration?

Which of the following is in the lanthanide family? a) uranium b) promethium c) silver d) gold