- How much energy is required to raise the hydrogen atom from the ground state n = 1 to the first excited state n = 2 ? What is the wavelength of the line emitted if the atom returned to the ground state from the excited state ?​

Which one of the following gases is not an important component of soil?

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.

How many moles of al3+ ions are in 1.25 moles of al2o3