Match List-I with List-II:

List-I (Element-Atomic number)		List-II (Position in periodic table)
(a)	Ra – 88	(i)	$4^{th}$ period, $13^{th}$ group
(b)	Ga – 31	(ii)	$6^{th}$ period, $6^{th}$ group
(c)	W – 74	(iii)	$5^{th}$ period, $10^{th}$ group
(d)	Pd – 46	(iv)	$7^{th}$ period, $2^{nd}$ group

Choose the correct answer from the options given below.

The position of an element in the periodic table can be determined using its atomic number and the nearest preceding noble gas.

(a) Ra ($Z = 88$): The preceding noble gas is Radon (Rn, $Z = 86$), which belongs to the $6^{th}$ period and $18^{th}$ group. The next two electrons enter the $7s$ orbital. Thus, Ra belongs to the $7^{th}$ period and $2^{nd}$ group. (a) $\rightarrow$ (iv)

(b) Ga ($Z = 31$): The preceding noble gas is Argon (Ar, $Z = 18$), which belongs to the $3^{rd}$ period. The next electrons fill the $4s$, $3d$, and $4p$ orbitals. The group number is $31 - 18 = 13$. Thus, Ga belongs to the $4^{th}$ period and $13^{th}$ group. (b) $\rightarrow$ (i)

(c) W ($Z = 74$): The preceding noble gas is Xenon (Xe, $Z = 54$), which belongs to the $5^{th}$ period. The next electrons fill the $6s$, $4f$ (14 elements), and $5d$ orbitals. The group number is $74 - 54 - 14 = 6$. Thus, W belongs to the $6^{th}$ period and $6^{th}$ group. (c) $\rightarrow$ (ii)

(d) Pd ($Z = 46$): The preceding noble gas is Krypton (Kr, $Z = 36$), which belongs to the $4^{th}$ period. The next electrons fill the $5s$ and $4d$ orbitals. The group number is $46 - 36 = 10$. Thus, Pd belongs to the $5^{th}$ period and $10^{th}$ group. (d) $\rightarrow$ (iii)

The correct matching is a-iv, b-i, c-ii, d-iii.

Answer: a-iv, b-i, c-ii, d–iii