Which of the following ions has the largest ionic radius? MCQ with Answer and Explanation

Which of the following ions has the largest ionic radius?
A. Na+
B. Mg2+
C. Al3+
D. F-
Answer: Option D
Solution (By JKSSB Mock Tests)
Na+, Mg2+, Al3+, and F- are isoelectronic species, each having 10 electrons. For isoelectronic ions, the ionic radius decreases as the nuclear charge (number of protons) increases because the greater positive charge pulls the same number of electrons closer. F- has the lowest nuclear charge (9), so it has the largest radius.

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More chemistry Questions

Question #1
Which of the following represents a disproportionation reaction?
A. Zn + CuSO4 -> ZnSO4 + Cu
B. CaCO3 -> CaO + CO2
C. N2 + 3H2 -> 2NH3
D. 2H2O2 -> 2H2O + O2

Correct Answer: Option D


Explanation:
A disproportionation reaction is a specific type of redox reaction where the same element in a single substance is simultaneously oxidized and reduced. In the decomposition of hydrogen peroxide (H2O2), oxygen has an oxidation state of -1. It is reduced to -2 in H2O and oxidized to 0 in O2.

This question belongs to: Science chemistry
Question #2
Ozonation of water is preferred over chlorination because:
A. It is cheaper.
B. It does not leave any harmful residual taste or toxic byproducts.
C. It is easier to transport.
D. It removes hardness.

Correct Answer: Option B


Explanation:
Ozonation is a powerful disinfection method that kills bacteria and viruses faster than chlorine. Unlike chlorine, ozone decomposes back into oxygen and does not leave a residual taste or form harmful chlorinated organic byproducts (like trihalomethanes), making it safer for drinking water.

This question belongs to: Science chemistry
Question #3
Which of the following compounds has a coordinate bond?
A. CH₄
B. H₂O
C. NH₃
D. O₃

Correct Answer: Option D


Explanation:
Ozone (O₃) has one coordinate bond; a central oxygen donates a lone pair to another oxygen. CH₄, NH₃, H₂O have ordinary covalent bonds, though NH₃ can donate a pair to form NH₄⁺.

This question belongs to: Science chemistry