Cobalt chloride is blue in dry state but in contact with moisture, it turns __________.

Yellow

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Pink

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Green

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Red

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Solution

The correct option is B Pink
Cobalt chloride paper test is the hygrometric test for transpiration. Dry cobalt chloride is blue, while moist one is pink. A filter paper slip can be dipped in 3 to 5 percent cobalt chloride and dried. It appears blue. The slip is placed over leaf surface and protected from atmospheric humidity by a glass slide or transparent tape. Change in colour of the filter paper slip from blue to pink indicates transpiration.

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(4) turned red

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(c) Hydrogen Chloride gas is not collected over water.

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(e) dry hydrogen chloride gas does not affect a dry strip of blue litmus paper but it turns red in the presence of a drop of water.

(f) hydrogen chloride gas is not collected over water.

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gas does not effect a dry strip of blue litmus paper but it turns red in the presence of a drop of water ?

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