Answer:
β-hydroxyaldehyde (an aldol) namely 3-Hydroxy butanal.
Explanation:
When acetaldehyde is treated with dil.NaOH it undergoes self condensation as it contains alpha-hydrogen atom in its compound forming β-hydroxyaldehyde (an aldol) namely 3-Hydroxy butanal. This compound upon further heating will eliminate a molecule of water forming aldol condensation product namely Crotonaldehyde Or But-2-en-al. see the diagram attached.
The correct answer is Crystals.
Unlike sugar, salt is not made out of crystals, but both salt and sugar are made out of atoms, that is molecules, and can have ions.
Answer:

Explanation:
Hello,
In this case, since at 60 °C, 108 grams of ammonium bromide are completely dissolved in 100 grams of water for a saturated solution, once it is cooled to 30 °C, wherein only 83.2 grams are completely dissolved in 100 grams of water, the following mass will precipitate:

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