The speed of light c = _______ m/s. Answer: $3 \times 10^{8}$

The threshold frequency is the _______ frequency required for the photoelectric effect. Answer: minimum

The Rydberg constant R_H = _______ $m^{-1}$. Answer: $1.097 \times 10^{7}$

The Balmer series falls in the _______ region of the spectrum. Answer: visible

Energy of the nth orbit: E_n = _______ eV. Answer: −13.6$Z^{2}$/$n^{2}$

Radius of nth orbit: r_n = _______ Å. Answer: 0.529$n^{2}$/Z

Total spectral lines from level n = _______. Answer: n(n−1)/2

de Broglie equation: λ = _______. Answer: h/mv

Heisenberg uncertainty: $\Delta x$ · $\Delta p$ ≥ _______. Answer: h/4π

For the 3p orbital: radial nodes = _______, angular nodes = _______. Answer: 1, 1

Electronic configuration of Cr = _______. Answer: [Ar] 3$d^{5}$ 4$s^{1}$

The maximum electrons in d subshell = _______. Answer: 10

Angular momentum in nth orbit (Bohr) = _______. Answer: nh/2π

For n=4: total orbitals = _______, max electrons = _______. Answer: 16, 32

Lyman series: n_{1} = ___, region = ___. Answer: 1, ultraviolet