List-I shows different radioactive decay processes and List-II provides possible emitted particles. Match each entry in List-I with an appropriate entry from List-II, and choose the correct option. | List-I | | List-II | | |---|---|---|---| | (P) | $_{92}^{238} U \rightarrow _{91}^{234} Pa$ | (1) | one $\alpha$ particle and one $\beta^{+}$ particle | | (Q) | $_{82}^{214} \mathrm{~Pb} \rightarrow _{82}^{210} \mathrm{~Pb}$ | (2) | three $\beta^{-}$ particles and one $\alpha$ particle | | (R) | $_{81}^{210} \mathrm{Tl} \rightarrow _{82}^{206} \mathrm{~Pb}$ | (3) | two $\beta^{-}$ particles and one $\alpha$ particle | | (S) | $_{91}^{228} \mathrm{~Pa} \rightarrow _{88}^{224} Ra$ | (4) | one $\alpha$ particle and one $\beta^{-}$ particle | | | | (5) | one $\alpha$ particle and two $\beta^{+}$ particles |

(A) $P \rightarrow 4, Q \rightarrow 3, R \rightarrow 2, S \rightarrow 1$

(B) $P \rightarrow 4, Q \rightarrow 1, R \rightarrow 2, S \rightarrow 5$

(C) $P \rightarrow 5, Q \rightarrow 3, R \rightarrow 1, S \rightarrow 4$

(D) $P \rightarrow 5, Q \rightarrow 1, R \rightarrow 3, S \rightarrow 2$

JEE Advanced · 2023 · 04 Jun 2023 · Paper 1 · Modern Physics

List-I shows different radioactive decay processes and List-II provides possible emitted particles. Match each entry in List-I with an appropriate entry from List-II, and choose the correct option.

List-I		List-II
(P)	$_{92}^{238} U \to_{91}^{234} P a$	(1)	one $α$ particle and one $β^{+}$ particle
(Q)	$_{82}^{214} Pb \to_{82}^{210} Pb$	(2)	three $β^{-}$ particles and one $α$ particle
(R)	$_{81}^{210} Tl \to_{82}^{206} Pb$	(3)	two $β^{-}$ particles and one $α$ particle
(S)	$_{91}^{228} Pa \to_{88}^{224} R a$	(4)	one $α$ particle and one $β^{-}$ particle
		(5)	one $α$ particle and two $β^{+}$ particles

(A) $P \to 4, Q \to 3, R \to 2, S \to 1$ ✓ Correct
(B) $P \to 4, Q \to 1, R \to 2, S \to 5$
(C) $P \to 5, Q \to 3, R \to 1, S \to 4$
(D) $P \to 5, Q \to 1, R \to 3, S \to 2$

Answer: (A)

Solution

For each decay, we use conservation of mass number and atomic number.

(P)

_{92}^{238} U \to_{91}^{234} P a

: Mass decreases by 4 (one

α

), atomic number decreases by 1 net. Since

α

decreases Z by 2, we need one

β^{-}

to increase Z by 1. Match: 4.

(Q)

_{82}^{214} P b \to_{82}^{210} P b

: Mass decreases by 4 (one

α

), Z unchanged. Since

α

decreases Z by 2, we need two

β^{-}

to restore Z. Match: 3.

(R)

_{81}^{210} T l \to_{82}^{206} P b

: Mass decreases by 4 (one

α

), Z increases by 1 net. Since

α

decreases Z by 2, we need three

β^{-}

to increase Z by 3 total. Match: 2.

(S)

_{91}^{228} P a \to_{88}^{224} R a

: Mass decreases by 4 (one

α

), Z decreases by 3 net. Since

α

decreases Z by 2, we need one

β^{+}

to decrease Z by 1 more. Match: 1.

Answer: (A)

P \to 4, Q \to 3, R \to 2, S \to 1

JEE Advanced · 2023 · 04 Jun 2023 · Paper 1 · Single correct option

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JEE Advanced · 2023 · 04 Jun 2023 · Paper 1 · Modern Physics

Solution

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