Question

Samir observed that when he washed his clothes a sample of water, scum is formed. Those scule sale
a) Calcium salts of long chain of carboxylic acid,
b) Magnesium salts of long chain of carboxylic acid
c) lead salt of long chain of carboxylic acid
d) either (a) or (b)
A Student strongly heats hydrated ferrous sulphate in a dry test tube. He would observe a:
licht green residue d) White residue​

Answer 1

Answer:

1st part is options ( a)

2nd is option (d)

Answer 2

Let us look at the answer:

Explanation:

Scum is formed when soap is dissolved in hard water. It forms a sticky substance detering the cleansing action of soap.

Hard water contains long hydrocarbon chain of salts of calcium and magnesium.

1st question option D

Heating hydrated ferrous sulphate crystals in a dry test tube: ferrous sulphate crystals liberates green colour.