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 |
Match the following:
Column I | Column II | ||
A. | X-rays | 1. | |
B. | Ultraviolet wave (UV) | 2. | |
C. | Long radio waves | 3. | |
D. | Microwave | 4. |
A | B | C | D | |
1. | 4 | 1 | 3 | 2 |
2. | 1 | 4 | 2 | 3 |
3. | 1 | 4 | 3 | 2 |
4. | 4 | 3 | 1 | 2 |
Assertion (A): | All isotopes of a given element show the same type of chemical behaviour. |
Reason (R): | The chemical properties of an atom are controlled by the number of electrons in the atom. |
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. |
Assertion (A): | A black body is an ideal body that emits and absorbs radiation of all frequencies. |
Reason (R): | The frequency of radiation emitted by a body goes from lower frequency to a higher frequency with an increase in temperature. |
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. |
Assertion (A): | It is impossible to determine the exact position and exact momentum of an electron simultaneously. |
Reason (R): | The path of an electron in an atom is clearly defined. |
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. |
The total number and mass of neutrons in 7 mg of 14C would be :
(Assume that mass of a neutron = 1.675 × 10–27 kg)
\(1 .\) \(2 . 41\) \(\times\) \(\left(10\right)^{21}\) \(,\) \(4 . 03\) \(\times\) \(\left(10\right)^{– 6}\) \(kg\)
\(2 .\) \(6 . 23\) \(\times\) \(\left(10\right)^{23}\) \(,\) \(1 . 67\) \(\times\) \(\left(10\right)^{- 21} kg\)
\(3 .\) \(1 . 22\) \(\times\) \(\left(10\right)^{22}\) \(,\) \(4 . 03\) \(\times\) \(\left(10\right)^{6}\) \(kg\)
\(4 . 2 . 41\) \(\times\) \(\left(10\right)^{21}\) \(,\) \(4 . 03\) \(\times\) \(\left(10\right)^{- 6}\) \(g\)
The wave number of a light whose time period is 2.0 × 10–10 s would be:
1. 16.66 m–1
2. 1.66 m–1
3. 32.34 m–1
4. 12.34 m–1
The number of photons of light with a wavelength of 4000 pm that provide 1J of energy would be:
Electromagnetic radiation of wavelength 242 nm is just sufficient to ionise sodium atom. The ionisation energy of sodium in kJ mol–1 is :
1. 494
2. 4.94
3. 516
4. 0.50