The radii of the first bohr orbit of H(rH), He+ (rHe+) and Li2+(rLi2+) are in the order:
1. rH = rHe+ = rLi+2
2. rH < rHe+ < rLi2+
3. rH > rHe+ > rLi2+
4. rHe+ < rH < rLi2+
The number of protons, neutrons and electrons in \( _{71}^{175}Lu\) respectively, are:
1. 104, 71 and 71
2. 71, 71 and 104
3. 175, 104 and 71
4. 71, 104 and 71
Assertion (A): | The splitting of spectral lines in an electric field is called the stark effect. |
Reason (R): | It is explained by Bohr's theory. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
Which of the following options does not represent ground state electronic configuration of an atom?
1.
2.
3.
4.
Match the ensuing rules with the corresponding statements:
Rules | Statements | ||
A. | Hund’s Rule | 1. | No two electrons in an atom can have the same set of four quantum numbers. |
B. | Aufbau Principle | 2. | Half-filled and completely filled orbitals have extra stability. |
C. | Pauli's Exclusion Principle | 3. | Pairing of electrons in the orbitals belonging to the same subshell does not take place until each orbital is singly occupied. |
D. | Heisenberg’s Uncertainty Principle | 4. | It is impossible to determine the exact position and exact momentum of a subatomic particle simultaneously. |
5. | In the ground state of atoms, orbitals are filled in the order of their increasing energies. |
A | B | C | D | |
1. | 3 | 5 | 1 | 2 |
2. | 1 | 2 | 3 | 4 |
3. | 3 | 5 | 1 | 4 |
4. | 4 | 5 | 3 | 2 |
Orbital having 3 angular nodes and 3 total nodes is:
1. 5 p
2. 3 d
3. 4 f
4. 6 d
The number of electrons plus neutrons in \(_{19}^{40}K^{+}\) is:
1. 38
2. 59
3. 39
4. 40
In a ground-state phosphorous atom in the gas phase, how many electrons have quantum numbers n = 3, l = 1, ml = –1?
1. 0
2. 1
3. 2
4. 3
If the velocity of an electron in Bohr’s first orbit is 3.19 x 106 ms-1, then the de Broglie wavelength associated with it would be:
1. 314 pm