Group Displacement Law

Q.

An element with atomic mass z has two isotopes having atomic masses (z-1) and (z+2). Find out the percentage abundance of heavier isotope.

Q.

During nuclear explosion, one of the products is ⁹⁰Sr with half-life of 28.1 years. If 1μg of ⁹⁰Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically.

Q. The number of $\alpha$ and $\beta$-particles emitted during the transformation of ${}_{90}T{h}^{232}$ to ${}_{82}{P}^{208}$ are respectively

1. 4, 2
2. 2, 2
3. 8, 6
4. 6, 4

Q. The number of alpha and $\beta$ particles emitted when ${}_{92}^{238}U$ is finally converted into ${}_{82}^{206}Pb$ is:

1. 2, 1
2. 4, 2
3. 8, 6
4. 6, 4

Q.

Write the properties of electrons.

Q. The position of element $RaC$ in the periodic table is:
${}_{88}^{226}Ra{\stackrel{-\alpha }{\to }}_{86}Rn\stackrel{-\alpha }{\to }RaA\stackrel{-\beta }{\to }RaB\stackrel{-\alpha }{\to }RaC$

1. ${13}^{th}$ group and $6^{th}$ period
2. ${16}^{th}$ group and $3^{rd}$ period
3. ${15}^{th}$ group and $7^{th}$ period
4. ${15}^{th}$ group and $6^{th}$ period

Q. The relative abundance of two isotopes of atomic masses 85 and 87 are 75% and 25% respectively. The average atom mass of element is:

1. 86
2. 40
3. 85.5
4. 75.5

Q. The number of alpha particles and beta particles emitted in the reaction 238Th90~212Bi83 respectively

Q. According to the nuclear reaction ${}_{4}Be{+}_{2}H{e}^4{\to }_6{C}^{12}{+}_0{n}^1$, mass number of (Be) atom is

1. 7
2. 6
3. 9
4. 4

Q. ${}_{90}T{h}^{232}$ belongs to III group. It emits an $\alpha$-particle. The daughter element belongs to

1. I group
2. II group
3. III group
4. IV group

Q. How many neutrons are present in the nucleus of Ra

1. 88
2. 226
3. 140
4. 138

Q. Number of $\alpha$- and $\beta$- particles emitted in 4n disintegration series is

1. $4\alpha ,4\beta$
2. $7\alpha ,4\beta$
3. $7\alpha ,7\beta$
4. $7\alpha ,5\beta$

Q. Which one of the following nuclear reaction is correct

1. ${}_6{C}^{13}{+}_1{H}^1{\to }_7{N}^{13}+{\beta }^{-}+v^{-}$
2. ${}_{11}N{a}^{23}{+}_1{H}^1{\to }_{10}N{e}^{20}{+}_{2}H{e}^4$
3. ${}_{13}A{l}^{23}{+}_0{n}^1{\to }_{11}N{a}^{23}+e^0$
4. None of these

Q.

The number of electrons in an element X is $15$ and the number of neutrons is $16$. Which of the following is the correct representation of the element?

1. ${}_{15}{}^{31}\mathrm{X}$

2. ${}_{16}{}^{31}\mathrm{X}$

3. ${}_{15}{}^{16}\mathrm{X}$

4. ${}_{16}{}^{15}\mathrm{X}$

Q. The number of $\alpha$ and $\beta$ - particles emitted in the nuclear reaction ${}_{92}{U}^{238}{\to }_{90}T{h}^{234}{\to }_{91}P{a}^{234}$ are respectively:

1. 2 and 1
2. 2 and 2
3. 1 and 2
4. 1 and 1

Q. How many $\alpha and\beta$ -particles are emitted when an atom of ${}_{90}T{h}^{232}$ undergoes disintegration to produce an atom of ${}_{82}T{h}^{208}$

1. 5, 3
2. 6, 4
3. 7, 5
4. 8, 6

Q.

A nucleus ${}_{11}N{a}^{24}$ emits a $\beta$-particle to change into magnesium(Mg). Write the symbolic equation for the process.

Q. for radioactive reaction 90% of reaction completes in 10 years.what will be its half life

Q. How many neutrons are present in the nucleus of Ra

1. 88
2. 226
3. 140
4. 138

Q.

If radioactive atom does one alpha and 2 beta decay, which ones of the following statements are true for this atom?
I. Its isotope is formed.
II. Its location in the periodic table does not change.
III. Its mass number decreases.

1. I, II are correct

2. Only I is correct
3. Only II is correct
4. All are correct.

Q. In the nuclear reaction ${}_{12}M{g}^{24}{+}_{2}H{e}^4{=}_0{n}^1+?$ The product nucleus is

1. ${}_{13}A{l}^{27}$
2. ${}_{14}S{i}^{27}$
3. ${}_{13}A{l}^{28}$
4. ${}_{12}M{g}^{25}$

Q. What happens to the position of an element in the periodic table when it emits an alpha particle?

1. changes to $2$ places further
2. no change
3. cant say
4. changes to $2$ places earlier

Q. $\begin{array}{c}180\\ 72\end{array}X\stackrel{2\alpha }{\to }\stackrel{\beta }{\to }\stackrel{\gamma }{\to }\begin{array}{c}A\\ Z\end{array}{X}^{\prime }$.Z and A are

1. 69, 172
2. 172, 69
3. 180, 70
4. 182, 68

Q. The atomic mass of Th is 232.18 and its atomic number is 90. In terms of its radioactive disintegration, 6 $\alpha$- and 4 $\beta$- particles are emitted. The mass number and atomic number of products is :

1. 192 78
2. 208, 82
3. 212, 86
4. 180, 72

Q. The number of neutrons in the parent nucleus which gives $N^{14}$ on $\beta$ -emission is:

1. 7
2. 14
3. 6
4. 8

Q. The periodic table consists of 18 groups. An isotope of copper, on bombardment with protons, undergoes a nuclear reaction yielding element X as shown below. To which group, element X belongs in the periodic table? ${}_{29}^{63}Cu{+}_1^{1}H\to 6_0^{1}n{+}_2^4\alpha +2_1^{1}H+X$

Q. In the reaction, $Po\stackrel{-\alpha }{\to }Pb\stackrel{-\beta }{\to }Bi$, if Bi, belongs to group 15, to which Po belongs

1. 14
2. 15
3. 13
4. 16

Q. A nuclide of an alkaline earth metal undergoes radioactive decay by emission of the $\alpha$-particles in succession. The group of periodic table to which the resulting daughter element belongs to :

1. group 4
2. group 6
3. group 16
4. group 14

Q. Uranium with a mass number 237 and atomic number 92, changes to a nucleus with atomic number 90 and mass number 233 on emission of:

1. $\beta$-particle
2. $\gamma$-particle
3. $\alpha$-particle
4. positron

Q. According to the nuclear reaction ${}_{4}Be{+}_{2}H{e}^4{\to }_6{C}^{12}{+}_0{n}^1$, mass number of (Be) atom is

1. 4
2. 9
3. 7
4. 6