What is the ratio of the speed of an electron in the first orbit of an \(\mathrm{H}\text-\)atom to the speed of light?
1. | \(\dfrac{1}{137}\) | 2. | \(137\) |
3. | \(\dfrac{1}{83}\) | 4. | \(\dfrac{1}{47}\) |
The Rutherford -particle experiment shows that most of the -particles pass through almost unscattered while some are scattered through large angles. What information does it give about the structure of the atom?
1. | Atom is hollow. |
2. | The whole mass of the atom is concentrated in a small center called the nucleus. |
3. | Nucleus is positively charged. |
4. | All of the above |
1. \(2000~\mathring{A}\)
2. \(4000~\mathring{A}\)
3. \(4500~\mathring{A}\)
4. \(9000~\mathring{A}\)
1. | \(5\rightarrow 4\) | 2. | \(3\rightarrow 2\) |
3. | \(2\rightarrow 1\) | 4. | \(3\rightarrow 1\) |
1. | 2. | ||
3. | 4. |
1. | \(145\) | 2. | \(160\) |
3. | \(172\) | 4. | \(157\) |
The de-Broglie wavelength of an electron in the second orbit of a hydrogen atom is equal to:
1. | The perimeter of the orbit. |
2. | The half of the perimeter of the orbit. |
3. | The half of the diameter of the orbit. |
4. | The diameter of the orbit. |