Representative (Main Group) Elements: Definition and Which Groups They Are
Chemistry · Periodic Classification Of Properties · NEET
Representative elements (also called main group elements) are the s-block plus the p-block elements. That means Groups 1, 2 and 13 to 18 of the periodic table. Memory hook: "Main group = s + p", so the d-block (transition) and f-block (inner-transition) metals are NOT representative elements.
Representative (main group) elements are the s-block (Groups 1 and 2) plus the p-block (Groups 13 to 18). The d-block transition metals and f-block inner-transition metals are excluded.
Your doubts, answered
What exactly are representative or main group elements?
NCERT says the p-block elements (Groups 13 to 18) together with the s-block elements (Groups 1 and 2) are called the representative elements or main group elements. So the two names mean the same thing. In short: main group = s-block + p-block.
Which groups count as representative elements?
Groups 1, 2, 13, 14, 15, 16, 17 and 18. That is the two s-block groups on the far left and the six p-block groups on the right. Groups 3 to 12 (the d-block transition metals) are left out.
Are transition metals (d-block) representative elements?
No. Transition elements (d-block, Groups 3 to 12) and inner-transition elements (f-block, the lanthanoids and actinoids) are NOT representative elements. Only s-block and p-block elements are. This is the single most common NEET mistake.
How do I spot a main group element from its electron configuration?
Look at the last orbital being filled. If the outermost electrons go into an s or p orbital (like ns1, ns2, or ns2 np1 to ns2 np6), it is a main group element. If the last electrons go into a d orbital (…3d… 4s2) or an f orbital, it is NOT main group.
Are noble gases representative elements?
Yes. Group 18 (noble gases) is part of the p-block, so noble gases are counted as representative elements. Their outer configuration is ns2 np6 (helium being the special case with just 1s2).
Is hydrogen a representative element?
Yes. Hydrogen is in the s-block (1s1), so by definition it is a representative element, even though its position in the table is unusual.
Why is this called 'representative'?
These elements show clear, regular periodic trends (in size, ionization enthalpy, valence, etc.), so they 'represent' typical periodic behaviour. Their valence is simply the number of outer electrons or eight minus that number. That neat pattern is why NEET loves testing them.
⚠️ The NEET trap ✗ Picking a d-block or f-block configuration (like [Ar]3d3 4s2 or [Rn]5f0 6d2 7s2) as a 'main group element'. ✓ Main group = s-block + p-block ONLY. [Ne]3s1 (Na, s-block) and [Kr]4d10 5s2 5p5 (I, p-block) are the main group ones. [Ar]3d3 4s2 (V), [Ar]3d10 4s1 (Cu) and [Rn]5f0 6d2 7s2 (Th) are transition / inner-transition, so they are NOT main group. 🧠 Last electron in s or p orbital = main group. Last electron in d or f orbital = out.
Real NEET questions
NEET 2025
Which among the following electronic configurations belong to main group elements? A. [Ne]3s1 B. [Ar]3d3 4s2 C. [Kr]4d10 5s2 5p5 D. [Ar]3d10 4s1 E. [Rn]5f0 6d2 7s2
A · D and E only
B · A, C and D only
C · B and E only
D · A and C only ✓
Solution: By the NCERT definition, main group = s-block + p-block. Identify each: A [Ne]3s1 is Na (s-block, main group); C [Kr]4d10 5s2 5p5 is I (p-block, main group). B [Ar]3d3 4s2 is V (d-block, transition); D [Ar]3d10 4s1 is Cu (d-block, transition); E [Rn]5f0 6d2 7s2 is Th (f-block/actinide, inner-transition). So the chemically correct main group set is A and C only (option D). Note: the printed official key marked option (C) B and E only, but on the standard NCERT definition the correct answer is A and C only.
Solved Periodic Classification Of Properties NEET PYQs
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Are representative elements and main group elements the same?
Yes, they are two names for the exact same set: the s-block plus the p-block elements (Groups 1, 2 and 13 to 18).
How many groups of representative elements are there?
Eight groups: 1 and 2 from the s-block, and 13, 14, 15, 16, 17, 18 from the p-block.
Do representative elements include metals and non-metals?
Yes. They include reactive metals (like Na, Mg), metalloids (like Si, As), non-metals (like Cl, O), and noble gases. The block only depends on which orbital fills last, not on metallic character.
Why do NEET questions test main group elements so often?
Because they show clean, predictable periodic trends. Their valence equals the number of outer electrons or eight minus it, and their properties change smoothly across a period, making them ideal for trend-based questions.
