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What makes caesium and potassium useful ...

What makes caesium and potassium useful as electrodes in photoelectric cells?

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The ionisation energies of caesium and potassium are very small. When light falls on the surface of metals, the energy present in them is absorbed by the atoms on the surface of metal. The energy of light is sufficient to make an atom to lose electron. This property makes caesium and potassium useful as electrodes in photoelectric cells.
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VGS PUBLICATION-BRILLIANT-THE s-BLOCK ELEMENTS -Short Answer Questions (4 Marks)
  1. Alkali metals and their salts impart characteristic colours to an oxid...

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  2. What makes caesium and potassium useful as electrodes in photoelectric...

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  3. Write a short note on the reactivity of alkali metals towards air.

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  4. Give any two uses for each of the following metal. (i) Lithium

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  5. Give any two uses for each of the following metal. (ii) Sodium.

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  6. Give an account of the properties of washing soda.

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  7. Mention some uses of sodium carbonate.

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  8. How do you obtain pure sodium chloride from a crude sample?

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  9. What do you know about Castner-Kellner process? Write the principle in...

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  10. Write a few applications of caustic soda.

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  11. Give an account of the biological importance of Na^(+) and K^(+) ions.

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  12. Mention the important uses of Mg metals.

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  13. Show that Be(OH)(2) is amphoteric in nature.

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  14. Write a note on the anomalous behaviour of beryllium.

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  15. Be shows diagonal relationship with Al. Disicuss.

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  16. What is Plaster of Paris? Write a short note on it.

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  17. In what ways lithium shows similarities to magnesium in its chemical b...

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  18. When an alkali metal dissolves in liquid ammonia the solution can acqu...

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  19. What happens when (i) Sodium metal is dropped in water?

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  20. What happens when (ii) Sodium metal is heated in a free supply of ai...

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