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Question
Which of the alkali metal is having least melting point?
Options
Na
K
Rb
Cs
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Solution
Cs
Explanation:
Atomic size increases as we move down the alkali group. As a result, the binding energies of their atoms in the crystal lattice decrease. Also, the strength of metallic bonds decreases on moving down a group in the periodic table. This causes a decrease in the melting point. Among the given metals, Cs is the largest and has the least melting point.
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