Question

The period number and group number of platinum in the long form of periodic table are respectively:

• A. 5, 11
• B. 5, 10
• C. 6, 11
• D. 6, 10

Hint:

For d-block elements: group number = (d electrons + s electrons).

Answer 1

The Correct Option is D

Step 1: Electronic configuration of Pt.
Platinum (Z=78) has the configuration [Xe] 4f¹⁴ 5d⁹ 6s¹.

Step 2: Identifying the period.
The highest principal quantum number is 6, placing it in Period 6.

Step 3: Identifying the group.
As a d-block element, the group number equals the sum of d and s valence electrons: 9 + 1 = 10.

Step 4: Transition metal classification rule.
Group number for transition metals is determined by total outermost d and s electrons.

Step 5: Confirming placement.
Pt belongs to Group 10 of the transition metals.

Step 6: Final conclusion.
Hence, Period 6 and Group 10.