MCQ
What is chemistry?
- AStudy of substances.
- BInvestigation of reactions and properties.
- CStudy of reactions to form new substances.
- DAll of the above.
Explanation:
Chemistry can be defined in many ways as it is study of substance, investigation of reactions and properties and also the study of reactions to form new substance.
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Assertion $(A):$ The ionic radii of $O ^{2-}$ and $Mg ^{2+}$ are same.
Reason $( R )$ : Both $O ^{2-}$ and $Mg ^{2+}$ are isoelectronic species.
In the light of the above statements, choose the correct answer from the options given below