Which is the correct order of increasing energy of the listed orbitals in the atom of titanium?
1. 3s 4s 3p 3d
2. 4s 3s 3p 3d
3. 3s 3p 3d 4s
4. 3s 3p 4s 3d

The number of d -electrons in Fe²⁺ (atomic number  Z = 26)  is different from the number of:
1. s-electrons in Mg (Z = 12)
2. p-electrons in Cl (Z = 17)
3. d-electrons in Fe (Z = 26)
4. p-electrons in Ne (Z = 10)

The angular momentum of electrons in d orbital is equal to:
1. $\sqrt{6}$ $\sout{h}$
2. $\sqrt{2}$$\sout{h}$
3. $2\sqrt{3}$ $\sout{h}$
4. 0 $\sout{h}$

What is the maximum number of orbitals that can be identified with the following quantum numbers?
n = 3, l = 1, m = 0

Calculate the energy corresponding to light of wavelength 45 nm:
(Planck's constant h = 6.63 × 10^–34 Js:
speed of light c = 3 × 10⁸ ms^–1)
1. 6.67 x 10¹⁵ J
2. 6.67 x 10¹¹ J
3. 4.42 x 10^-15 J
4. 4.42 x 10^-18 J

Based on equation E = –2.178 × 10^–18J, $\frac{{\mathrm{Z}}^2}{{\mathrm{n}}^2}$ certain conclusions are written. Which of them is not correct?

Maximum number of electrons in a subshell with l = 3 and n = 4 is:

1. 14

2. 16

3. 10

4. 12