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प्रश्न
The alkali metals are low melting. Which of the following alkali metal is expected to melt if the room temperature rises to 30°C?
पर्याय
Na
K
Rb
Cs
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उत्तर
Cs
Explanation:
Among alkali metals, melting point decreases as the strength of metallic bonding decreases with increasing size of the atom. Thus, Cs has the lowest melting point (28.5°C) and will melt at 30°C.
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संबंधित प्रश्न
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| List-I | List-II |
| (Metal) | (Emitted light wavelength (nm)) |
| (a) Li | (I) 780.0 |
| (b) Na | (II) 455.5 |
| (c) Rb | (III) 670.8 |
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