Reactivity | MCQs

Explanation

In moving down to the halogen group E.N. decreases hence Iodine has the lowest electronegativity.

DETAIL ANSWER:

 iodine has the lowest electronegativity.

Fluorine has the highest electronegativity followed by chlorine and bromine,

and then with the least reactivity, we have iodine, among the given options.

Hence, option D is correct.

Note: The noble gases i.e. group 18 elements have no electronegativity.

Explanation

As we move down the alkali metal group, atomic size increases, making the outer electron easier to lose.

This leads to greater reactivity, especially for metals like potassium and cesium.

Explanation

Alkali metals (such as lithium, sodium, potassium, etc.) act as reducing agents.

They readily lose their single valence electron to form positive ions, which means they donate electrons in reactions

Explanation

The reactivity of aldehydes towards nucleophilic addition depends on the size of the alkyl group attached to the carbonyl carbon.

Formaldehyde (HCHO) has no alkyl groups attached to the carbonyl carbon, making it the most reactive

Because there is no steric hindrance, and the electron-donating effect is minimal.

Explanation

The correct ascending order of reactivity of alkyl halides is F, Cl, Br, I, with fluorine being the least reactive and iodine being the most reactive.

Reactivity increases down the group as bond strength decreases.