Home / Exams / CISF / CISF_2026 / Question
CISF · 2026 Science & Technology › Physics & Chemistry
Consider the following: 1. Ionic radius order : Na+ < Mg2+ < Al3+ < Si4+ 2. Atomic radius order : Si < Al < Mg < Na 3. Effective nuclear charge : Na < Si < Mg < Al Which of the above is/are correct?
🔎 The pattern behind this question
This is the same idea UPSC keeps returning to. Start a free trial to see the answer and the full map.
Across examsCISF 2

Study how UPSC repeats — not just the papers

₹199 / 1 year · Founding Member

Full access unlocks the three things no PYQ PDF gives you:
① Cross-exam learning — see the same idea recur across CSE, CAPF, CDS and NDA.
② Topic evolution — how each idea is framed, year by year.
③ Question intelligence — every PYQ + answer, linked to related concepts and similar questions.

e.g. Round Table Conference: CDS 2017 → CSE 2017 → … → CAPF 2024

15 days free, no card required — then ₹199 for 1 year.

Start your 15-day free trial →
💬 Feedback

Send feedback