Gamma Decay

Q.

What is the difference between shells, subshells and orbitals??

Q. The maximum number of electrons in a subshell is given by the expression

1. 2l + 1
2. 2
3. 4l + 2
4. 4l – 2

Q. Which of the statements is/are true regarding gamma radiation?

1. Gamma radiations can be a consequence of a nucleus transitioning from higher energy state to ground state.
2. Gamma radiations are electromagnetic in nature.
3. Gamma radiations are high energy electrons.
4. Gamma radiations are high energy photons.

Q. Radioactive substances emit $\gamma$-rays, which are

1. + ve charged particle

2. – ve charged particle

3. Massive particle
4. Packet of energy

Q. In radioactive decay ${}_{90}T{h}^{234}\to {}_{92}T{h}^{234}$ the number of $\alpha$ and $\beta$ - particles emitted respectively are

1. $1,2$
2. $2,0$
3. $0,2$
4. $2,1$

Q. What is X in the following nuclear reaction ${}_7{N}^{14}{+}_1{H}^1{\to }_8{O}^{15}+X$

1. ${}_{+1}{e}^0$
2. ${}_0{n}^1$
3. $\gamma$
4. ${}_{-1}{e}^0$

Q. A radioactive nucleus will not emit

1. Alpha and beta rays simultaneously
2. Beta and gamma rays simultaneously
3. Gamma and alpha rays

4. Gamma rays only

Q. $A_Z^M\to B_{Z-1}^{M-12}$
The number of $\alpha$ and $\beta$ particles emitted in the above conversion is

1. $2\alpha ,4\beta$
2. $5\alpha ,6\beta$
3. $\alpha ,3\beta$
4. $3\alpha ,5\beta$

Q. A radioactive source emits three types of radiations.When the particle of one of these types becomes neutral, they are found to be the atoms of a rare gas. Name this rare gas.

1. Hydrogen
   
2. Tritium
   
3. Deuterium
   
4. Helium
   

Q. $\beta$-emission is always accompanied by :

1. formation of antineutrino and $\alpha$-particle
2. emission of $\alpha$-particle and $\gamma$-ray
3. formation of antineutrino and $\gamma$-ray
4. formation of antineutrino and positron

Q. Assertion :Nuclide ${}_{13}{Al}^{30}$ is less stable than ${}_{20}{Ca}^{40}$. Reason: Nuclides having odd number of protons and neutrons are generally unstable.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. A Geigger Muller counter is used to study the radioactive process. In the absence of eadioactive substance A, it counts 3 disintegration per second (dps). At the start in the presence of A, it records 23 dps; and after 10 min 13 dps.
i. What does it count after 20 min ?
ii. What is the half life of A ?

1. 5 dps, 5 min
2. 5 dps, 20 min
3. 8 dps, 10 min
4. 5 dps, 10 min

Q. In the nuclear transmutation, ${}_4^{9}Be+X{\to }_4^{8}Be+Y$ X and Y are:

1. $(\gamma ,n)$
   
2. $(p,D)$
3. $(n,D)$
4. $(\gamma ,p)$

Q. A human body required $0.01M$, activity of radioactive substance after $24$ hours. Half life of radioactive substance is $6$ hours. Then injection of maximum activity of radioactive substance that can be injected.

1. $0.08M$
2. $0.04M$
3. $0.16M$
4. $0.32M$

Q. Give one example each of (a) $\alpha -emission$, (b) ${\beta }^{+}-emission$, and (c) $K-capture$. Write the equation for these nuclear changes.

Q. How many $\alpha$- and $\beta$-particles should be emitted from a radioactive nuclide so that an isobar is formed?

1. $1\alpha ,1\beta$
2. $1\alpha ,2\beta$
3. $n\beta$
4. $2\alpha ,2\beta$

Q. A sample of radioactive material has an apparently constant activity of $2000$ dis/min. By chemcial means, the material is separated into two fractions, one of which has an initial activity of $1000$ dis/min. The other fraction decays with a $24$-hour half-life. Estimate the total activity in both samples $48$ hours after the separation. Explain your estimate.

Q. A chemist prepares 1.00 g of pure ${}_6^{11}C$. This isotope has half-life of 21 min, decaying by equation:
${}_6^{11}C{⟶}_5^{11}B{+}_1^{0}e$
What is rate of disintegration per second (dps) at start?

1. $3\times {10}^{19}$ dps
2. $4\times {10}^{19}$ dps
3. $6\times {10}^{19}$ dps
4. None of these

Q. Which of the following will definitely emit only $\gamma$-radiation?

1. ${}_{92}^{238}\text{U}$
2. ${}_6^{14}\text{C}$
3. ${}_1^3\text{H}$
4. ${}^{60m}\text{Co}$

Q. For the nuclear reaction, ${}_{12}^{24}Mg{+}_1{D}^2\to \alpha +?$, the missing nucleide is:

1. ${}_{11}^{23}Na$
2. ${}_{11}^{22}Na$
3. ${}_{12}^{23}Mg$
4. ${}_{12}^{26}Mg$

Q. What happens to the mass number of an element when $\gamma$-radiation is emitted ?

1. increases
2. cant say
3. no change
4. decreases

Q. Nuclear reactions accompained with emission of neutron(s) are :

1. ${}_{13}^{27}Al{+}_2^{4}He{\to }_{15}^{30}P$
2. ${}_{15}^{30}P{\to }_{14}^{30}Si{+}_1^{0}e$
3. ${}_{96}^{241}Am{+}_2^{4}He{\to }_{97}^{244}Bk{+}_1^{0}e$
4. ${}_6^{12}Al{+}_1^{1}H{\to }_7^{13}N$

Q. When nucleus of an electrically neutral atom undergoes a radioactive decay process, it will remain neutral after the decay if the process is

1. $\alpha$ -decay
2. ${\beta }^{\oplus }$ -decay
3. $\gamma$ -decay
4. K-capture process

Q. Match the List-I and List-II and select the correct answer using the codes given below the lists:

List-I Isotope	List-II Characteristics
$\left(A\right)$ ${}_{20}^{40}Ca$	$\left(i\right)$ Unstable, $\alpha$-emitter
$\left(B\right)$ ${}_{53}^{133}I$	$\left(ii\right)$ Unstable, $\beta$-emitter
$\left(C\right)$ ${}_{53}^{121}I$	$\left(iii\right)$ Unstable, positron emitter
$\left(D\right)$ ${}_{90}^{232}Th$	$\left(iv\right)$ Stable

1. $A-i,B-ii,C-iii,D-iv$
2. $A-iv,B-ii,C-iii,D-i$
3. $A-iv,B-iii,C-ii,D-i$
4. $A-i,B-iii,C-ii,D-iv$

Q. The nuclear reaction involving the bombardment reaction, ${}_{20}^{40}Ca(n,\alpha )$ is as follows:

1. ${}_{20}^{40}Ca{+}_0^{1}n{⟶}_{18}^{37}Ar{+}_2^{4}He$
2. ${}_{20}^{40}Ca{+}_0^{1}n{⟶}_{17}^{37}Ar{+}_3^{4}He$
3. None of these
4. ${}_{20}^{40}Ca{+}_0^{1}n{⟶}_{19}^{37}Ar{+}_1^{4}He$

Q. In the nuclear transmutation, ${}_4^{9}Be+X{\to }_4^{8}Be+Y$ X and Y are:

1. $(\gamma ,n)$
   
2. $(p,D)$
3. $(n,D)$
4. $(\gamma ,p)$

Q. A photon of gamma radiation knocks out a proton from ${}_{12}M{g}^{24}$ nucleus to form:

1. the isobar of parent nucleus
2. the nuclide ${}_{11}N{a}^{23}$
3. the isotopes of parent nucleus
4. the isobar of ${}_{11}N{a}^{23}$

Q. A photon of hard gamma radiation knocks a proton out of $\begin{array}{c}24\\ 12\end{array}$ nucleus to form

1. The isotope of parent nucleus
2. The isobar of parent nucleus
3. The nuclide $\begin{array}{c}23\\ 11\end{array}Na$
4. The isobar of $\begin{array}{c}23\\ 11\end{array}Na$

Q. When ${}_{92}{U}^{238}$ undergoes an $\alpha$-particle decay then incorrect option for daughter nuclei is:

1. group number in periodic table decreases
2. mass number decrease by 4
3. $n/p$ ratio increases
4. isodiapher species is formed

Q. The nucleus ${}_Z^{A}Y$ goes through gamma decay. What shall be the product?

1. ${}_{Z-1}^{A-1}X$
2. ${}_{Z-1}^{A}X$
3. ${}_Z^{A-1}Y$
4. ${}_Z^{A}Y$