Question

27. A student took four test tubes P Q R and S and filled about 8mL of distilled water in each. Thereafter, he declared equal amounts of MgSO_ (4) in Na_ (2) SO_ (4) Q in test tube P, K_ (2) SO_ (4) R in CaSO_ (4) S. By mixing equal amount of soap solution in each test tube and dissolving it properly, the test tubes in which it will receive adequate amount of foam are: (a) P and Q (b) P and R (c) PQ and S (d) QR and S​

Answer 1

Explanation:

Soaps are sodium or potassium salts of long chain fatty acids. With Ca and Mg, soap forms insoluble precipitate called scum. However, sodium (P) and potassium (Q) sulphates help in the formation of lather.

Hence, option A is correct.

Answer 2

Explanation:

i think c option hoga (pq and s)