Q. No.Why are the symbols ⁷⁹₃₅Br, and ⁷⁹Br are considered acceptable, whereas ³⁵₇9Br and ³⁵Brand are not acceptable representations of bromine?
| 1. | The general convention for representing an element along with its atomic number (A) and atomic mass (Z) is |
| 2. | The general convention for representing an element along with its atomic mass (A) and atomic number (Z) is |
| 3. | The general convention for representing an element along with its wavelength (A) and frequency (Z) is |
| 4. | The general convention for representing an element along with its isotopes (A) and atomic number (Z) is |
The atomic number of elements whose outermost electronic configuration are represented by 3s1 and 2p5 respectively, is:
| 1. | 9, 7 | 2. | 9, 11 |
| 3. | 11, 5 | 4. | 11, 9 |
A certain particle carries 2.5 × 10–16 C of static electric charge. The number of electrons present in it would be:
| 1. | 1460 | 2. | 1350 |
| 3. | 1560 | 4. | 1660 |
If the diameter of a carbon atom is 0.15 nm, the number of carbon atoms that can be placed side by side in a straight line across the length of the scale of length 20 cm long will be:
| 1. | 1.33 × 107 | 2. | 5.46 × 108 |
| 3. | 1.33 × 109 | 4. | 2.36 × 108 |
What is the number of zinc atoms present in a linear arrangement of length 1.6 cm, given that the diameter of a zinc atom is 2.6 Å?
1. 5.153 × 107
2. 6.153 × 107
3. 4.153 × 109
4. 6.153 × 103
2 × 108 atoms of carbon are arranged side by side. The radius of a carbon atom if the length of this arrangement is 2.4 cm would be :
1. 7.0 × 10–11 m
2. 5.0 × 10–11 m
3. 8.0 × 10–11 m
4. 6.0 × 10–11 m
Yellow light emitted from a sodium lamp has a wavelength (λ) of 580 nm. The frequency (ν) and wave number of this yellow light would be, respectively:
1. 517 × 1014 s–1 , 172 × 106 m–1
2. 6.17 × 1014 s–1 , 1.72 × 106 m–1
3. 4.17 × 1014 s–1 , 2.72 × 106 m–1
4. 5.17 × 1014 s–1 , 1.72 × 106 m–1
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
In Rutherford's \(\alpha\)-particle scattering experiment, a thin foil of heavy metals like gold or platinum is typically used. If a lighter metal foil, such as aluminum, were used instead, how would the observed deflection patterns change?
1. The same results will be observed
2. More deflection would be observed
3. There will not be enough deflection
4. None of the above
The incorrect statement regarding the characteristics of X-rays is :
1. The radiation can ionize the gas
2. It causes a fluorescence effect on ZnS
3. It is deflected by electric and magnetic fields
4. Have a shorter wavelength than ultraviolet rays
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