SSC
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The reactivity decreases
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Strength of nucleus to attract an electron into the valence shell increases
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Electropositivity decreases
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The single valence electron becomes more weakly pulled by the nucleus
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Detailed explanation-1: -The correct answer is Increases. Alkali metals are the elements present in group 1 in the periodic table. They are very reactive metals and their reactivity increases as we move down the group from top to bottom because of an increase in the atomic size.
Detailed explanation-2: -Both the melting and boiling points decrease down the group. When any of the Group 1 metals is melted, the metallic bond is weakened enough for the atoms to move more freely, and is broken completely when the boiling point is reached.
Detailed explanation-3: -All the alkali metals-lithium, sodium, potassium, and so on-have only one electron in their valence shell. Because this one electron is likely to be far from the nucleus, it feels little attraction to the atom. The result: Alkali metals tend to lose this electron when they participate in reactions.