Q. No.Identify the pairs which are not isotopes?
(a) \(_{6}^{12}X, \ _{6}^{13}Y\)
(b) \(_{17}^{35}X, \ _{17}^{37}Y\)
(c) \(_{6}^{14}X, \ _{7}^{14}Y\)
(d) \(_{4}^{8}X, \ _{5}^{8}Y\)
1. (a), (d)
2. (b), (c)
3. (c), (d)
4. (b), (d)
1. (a), (d)
2. (b), (c)
3. (c), (d)
4. (b), (d)
Match the quantum numbers with the information provided by these numbers:
| Quantum number | Information provided | ||
| A. | Principal quantum number | (i) | Orientation of the orbital |
| B. | Azimuthal quantum number | (ii) | The energy and size of the orbital |
| C. | Magnetic quantum number | (iii) | Spin of electron |
| D. | Spin quantum number | (iv) | The shape of the orbital |
Choose the correct codes:
1. A-(ii),B-(iii),C-(iv),D-(i)
2. A-(ii),B-(iv),C-(i),D-(iii)
3. A-(ii),B-(i),C-(iv),D-(iii)
4. A-(ii),B-(iii),C-(i),D-(iv)
Which of the following statements about the electron is incorrect?
| 1. | It is a negatively charged particle. |
| 2. | The mass of electron is equal to the mass of neutron. |
| 3. | It is a basic constituent of all atoms. |
| 4. | It is a constituent of cathode rays. |
Which pair of ions has the same electronic configuration?
| 1. | \(Cr^{3+}, Fe^{3+}\) | 2. | \(Fe^{3+}, Mn^{2+}\) |
| 3. | \(Fe^{3+}, Co^{3+}\) | 4. | \(Sc^{3+}, Cr^{3+}\) |
The nuclei of which one of the following pairs are isotones:
| 1. | \(34 \mathrm{Se}^{74},{ }_{31} \mathrm{Ga}^{71}\) | 2. | \({ }_{38} \mathrm{Sr}^{84},{ }_{38} \mathrm{Sr}^{86}\) |
| 3. | \({ }_{42} \mathrm{Mo}^{92},{ }_{40} \mathrm{Zr}^{92}\) | 4. | \({ }_{20} \mathrm{Ca}^{40},{ }_{16} \mathrm{~S}^{32}\) |
If uncertainty in position and momentum are equal, then the minimum uncertainty in velocity will be:
| 1. | \(\dfrac{1}{m} \sqrt{\dfrac{h}{\pi}} \) | 2. | \(\sqrt{\dfrac{h}{\pi}} \) |
| 3. | \(\dfrac{1}{2 m} \sqrt{\dfrac{h}{\pi}} \) | 4. | \(\dfrac{h}{4 \pi} \) |
Consider the following sets of quantum numbers :
| \(n\) | \(l\) | \(m\) | \(s\) | |
| (i) | 3 | 0 | 0 | +1/2 |
| (ii) | 2 | 2 | 1 | -1/2 |
| (iii) | 4 | 3 | -2 | +1/2 |
| (iv) | 1 | 0 | -1 | +1/2 |
| (v) | 3 | 4 | 3 | -1/2 |
Which of the following sets of quantum number is not possible?
1. (i), (ii), (iii) and (iv)
2. (ii), (iv) and (v)
3. (i) and (iii)
4. (ii), (iii) and (iv)
The quantum number of four electrons are given below :
| I. | n = 4, l=2 , ml = -2, ms = \(-\frac{1}{2}\) |
| II. | n=3, l=2, ml = 1, ms = \(+\frac{1}{2}\) |
| III. | n=4 , l=1, ml = 0, ms = \(+\frac{1}{2}\) |
| IV. | n=3, l=1, ml=1, ms=\(-\frac{1}{2}\) |
The correct order of their increasing energies is:
1. I < III < II < IV
2. IV < II < III < I
3. I < II < III < IV
4. IV < III < II < I
In \(_{35}^{80}Br\), the number of protons, neutrons, and electrons are:
1. 25, 45, 45
2. 35, 45, 35
3. 45, 45, 35
4. 80, 35, 35
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