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On exposure to air, sodium hydroxide bec...

On exposure to air, sodium hydroxide becomes liquid and after sometime it changes to white power. Explain.

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Sodium hydroxide continuously absorbs moisture and `CO_(2)` present in the air thus formaing sodium carbonate solution. A stage reaches when the solution becomes saturated and crystals are formed. These crystals, with the passage of time, lose water of crystallisation (efforescence) and crumble to white power.
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CENGAGE CHEMISTRY ENGLISH-S-BLOCK GROUP 1 - ALKALI METALS-Ex 4.1 (Subjective)
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  2. Alkali metals are paramagnetic but their salts are dimagnetic. Explain...

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  3. Give reasons for the following. LiI has lower melting point than LiF...

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  4. The Haber process can be represented as follows

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  5. Why does the reaction. proceed better with KF than with NaF ?

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  6. why lithium is kept wrapped in paraffin wax and not stored in kerosene...

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  7. When is a cation highly polarising? Which alkali metal cation has the ...

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  8. Why cesium can be used in photoelectric cell, while lithium cannot be ...

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  9. Give reason for the decreasing order of the conductivity of the follow...

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  10. NaHCO(3) and NaOH cannot exist together in solution. Why ?

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  11. On exposure to air, sodium hydroxide becomes liquid and after sometime...

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  12. Alkali metals are obtained by the electrolysis of the molten salts and...

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  13. What happens when: a. Potassium metal is dropped in water b. Potas...

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  14. How is sodium carbonate manufactured by Solvay's process? Draw a schem...

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  15. a. Describe one method of manufacture of castic soda. b. What happen...

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  16. Answer the following: Give the name of the hardest alakli metal.

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  17. Explain the following: a. Alkali metals are paramagnetic, but their ...

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  18. Identify (A) and (B) in the following: KO(2)+S overset(Delta)rarr (A)...

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  19. LiOH has been used by astronauts. Explain the use with the help of rea...

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  20. Give the composition and action of backing powder.

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