12. Change of Na,CO, 10 H,O to Na,CO, H,0 on exposure to air is called

1.	12. Change of Na,CO, 10 H,O to Na,CO, H,0 on exposure to air is called(A) efflorescence (B) effervescence(C) fluorescence(D) luminescence
Answer» A.efflorescence is the answee Efflorescence is a phenomenon where certain crystalline salts lose part or all of their water of crystallization when exposed to the atmosphere to form the anhydrous salts or what is called lower dehydrate. An example of efflorescent salt is is washing soda (sodium carbonate decahydrate) that loses nine out of its ten molecules of water of crystallization when exposed to the atmosphere. Na2CO3.10H2O(s) → Na2CO3.H2O(s) + 9H2O(g) visible effect... clear glassy crystals fall apart to white powder.

12. Change of Na,CO, 10 H,O to Na,CO, H,0 on exposure to air is called(A) efflorescence (B) effervescence(C) fluorescence(D) luminescence

Answer»

A.efflorescence is the answee

Efflorescence is a phenomenon where certain crystalline salts lose part or all of their water of crystallization when exposed to the atmosphere to form the anhydrous salts or what is called lower dehydrate. An example of efflorescent salt is is washing soda (sodium carbonate decahydrate) that loses nine out of its ten molecules of water of crystallization when exposed to the atmosphere.

Na2CO3.10H2O(s) → Na2CO3.H2O(s) + 9H2O(g)

visible effect... clear glassy crystals fall apart to white powder.

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