- 1(current)
Q. No.
If the mass of the iron nucleus is \(55.85~\text{u}\) and \(\mathrm{A} = 56\), the nuclear density of the iron is:
| 1. | \(2.27\times10^{17}~\text{kg m}^{-3}\) |
| 2. | \(1.36\times 10^{15}~\text{kg m}^{-3}\) |
| 3. | \(3.09\times10^{17}~\text{kg m}^{-3}\) |
| 4. | \(4.11\times10^{15}~\text{kg m}^{-3}\) |
The energy equivalent of \(1\) g of substance is:
| 1. | \(8.3\times10^{13}~\text{J}\) | 2. | \(9\times10^{13}~\text{J}\) |
| 3. | \(7.7\times10^{13}~\text{J}\) | 4. | \(11\times10^{13}~\text{J}\) |
We are given the following atomic masses:
\({ }_{92}^{238} \mathrm{U}=238.05079~\text{u},{ }_2^4 \mathrm{He}=4.00260~\text{u} \\ { }_{90}^{234} \mathrm{Th}=234.04363~\text{u},{ }_1^1 \mathrm{H}=1.00783~\text{u}\\ { }_{91}^{237} \mathrm{~Pa}=237.05121~\text{u} \)
Here the symbol \(\mathrm{Pa}\) is for the element protactinium \((Z=91)\).
The energy released during the alpha decay of \({}^{238}_{92}\mathrm{U}\) is:
1. \(6.14~\text{MeV}\)
2. \(7.68~\text{MeV}\)
3. \(4.25~\text{MeV}\)
4. \(5.01~\text{MeV}\)
We are given the following atomic masses:
\({ }_{92}^{238} \mathrm{U}=238.05079~\text{u},{ }_2^4 \mathrm{He}=4.00260~\text{u} \\ { }_{90}^{234} \mathrm{Th}=234.04363~\text{u},{ }_1^1 \mathrm{H}=1.00783~\text{u}\\ { }_{91}^{237} \mathrm{~Pa}=237.05121~\text{u} \)
Here the symbol Pa is for the element protactinium \((Z=91)\).
Then:
| 1. | \({}_{92}^{238}\mathrm{U}\) can not spontaneously emit a proton. |
| 2. | \({}_{92}^{238}\mathrm{U}\) can spontaneously emit a proton. |
| 3. | The \(Q\text-\)value of the process is negative. |
| 4. | Both (1) and (3) are correct. |
The energy required in \(\text{MeV/c}^2 \) to separate \({ }_8^{16} \mathrm{O}\) into its constituents is:
(Given: mass defect for \({ }_8^{16} \mathrm{O}=0.13691~ \text{amu}\))
| 1. | \(127.5\) | 2. | \(120.0\) |
| 3. | \(222.0\) | 4. | \(119.0\) |
Which one of the following is incorrect?
| 1. | A chemical equation is balanced in the sense that the number of atoms of each element is the same on both sides of the equation. |
| 2. | The number of atoms of each element is not necessarily conserved in a nuclear reaction. |
| 3. | The number of protons and the number of neutrons are conserved in each nuclear reaction. |
| 4. | Mass-energy interconversion takes place only in nuclear reactions and never in the chemical reaction. |
- 1(current)
Q. No.
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