Formalin consists of a mixture of formaldehyde, methyl alcohol and water. Percentage of water in it is:
Correct answer: A. 63%
- A. 63%
- B. 50%
- C. 52%
- D. 8%
Explanation
Formalin is a solution of formaldehyde (CH₂O) in water, and its concentration is often expressed in terms of percentage by weight. The most common concentration of formalin used in laboratories is 37% w/w, meaning 37% of the solution is formaldehyde, and the rest is water.Let's assume the percentage of formaldehyde in the given solution is 37%. The remaining percentage would be the water content.Water percentage = 100% - Percentage of formaldehydeWater percentage = 100% - 37% = 63%
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About Aldehydes and Ketones
Aldehydes and ketones contain the polar carbonyl group, but aldehydes are generally more readily oxidised and more reactive than ketones. Coverage includes preparation by oxidation or reduction routes, nucleophilic addition of reagents such as hydrogen cyanide and bisulfite, and tests that distinguish aldehydes from ketones.
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