Which of the following cations of alkali metals has least heat of hydration?
Correct answer: D. Cs+
- A. Li+
- B. Na+
- C. K+
- D. Cs+
Explanation
When considering the heat of hydration, the size and charge density of cations play a crucial role. In this case, Cesium ion (Cs+) stands out as it is the largest among alkali metal ions with the lowest charge density. This weak attraction to water molecules leads to the least heat of hydration. Therefore, option D is correct.Options A, B, and C are incorrect as they each have smaller sizes or higher charge densities compared to Cesium ion, resulting in higher heat of hydration values.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Reactions of Group I Elements
Group I elements have one valence electron, so their reactivity increases down the group as ionisation energy decreases. Their reactions with water, oxygen, hydrogen and halogens produce hydroxides, oxides, hydrides and halides, while the behaviour of lithium differs from the heavier metals because of its small ionic size.
Practise s-Block and p-Block Elements
1,361 free s-Block and p-Block Elements MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Reactions of Group I Elements questions
Which of the following oxide is formed by alkali metals?
Li2CO3 is thermally unstable whereas other Group-I carbonates are stable. Predict the reason.
Nitrates of which pair gives different products on thermal decomposition___________________?
Heat of solution of LiCl is,
Carbonates of sodium are stable but carbonates of lithium are less stable because of?
Which of the following is the least reactive alkali metal?