Q. No.Which of the following statement is not correct about the characteristics of cathode rays?
| 1. | They start from the cathode and move towards the anode |
| 2. | They travel in straight line in the absence of an external electrical or magnetic field |
| 3. | Characteristics of cathode rays do not depend upon the material of electrodes in cathode ray tube |
| 4. | Characteristics of cathode rays depend upon the nature of gas present in the cathode ray tube |
1. 2.4 ×10–19 g
2. 2.4 ×10–27 g
3. 2.4 ×10–24 g
4. None of the above.
Correct statement about the properties of the atom explained by the Thomson
model of an atom is:
| 1. | Overall neutrality of atom |
| 2. | Spectra of a hydrogen atom |
| 3. | Position of electrons, protons, and neutrons in an atom |
| 4. | Stability of atom |
Which of the following conclusions could not be derived from Rutherford's -particle scattering experiment?
| 1. | Most of the space in the atom is empty. |
| 2. | The radius of the atom is about 10-10 m while that of a nucleus is 10–15 m. |
| 3. | Electrons move in circular path of fixed energy called orbits. |
| 4. | Electrons and the nucleus are held together by electrostatic forces of attraction. |
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
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
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 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 |
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 |
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
© 2024 GoodEd Technologies Pvt. Ltd.