some important man made materials - Category wise Question and Answer Practice Test with Solutions

Question : 11

What is the reason for white cement to be white?

a) It does not contain iron

b) It does not contain silicon

c) It does not contain carbon

d) It does not contain calcium

Question : 12

Scurvy is caused due to the deficiency of vitamin

a) K

b) C

c) B1

d) A

Question : 13

Alkaline hydrolysis of esters is known as

a) dehydration

b) saponification

c) esterification

d) alkalination

Question : 14

By which one among the following mechanisms, soap removes dirt (soil) from cloth?

a) Soap takes away the oily part of the soil and thus separates the soil from the cloth

b) Soap reacts with soil and converts them into soluble silicates

c) Soap dissolves the soil as such

d) The soap molecules bind with the soil, lift the soil and keep it suspended which can then be rinsed away

Question : 15

Consider the following statements

1. Soap cannot be used in acidic water.
2. Ionic part of a soap is —COO^– · Na⁺ .
3. Soap dissolves in water faster then detergent.

a) 3 only

b) 2 and 3

c) 1 and 2

d) 1 only