Question

Bakelites are
A Rubber
B Rayon
C Resin
D Plasticizers

Answer 1

Hint: Bakelite is a thermosetting plastic polymer, which is prepared (set) by heating phenol and formaldehyde in the presence of catalysts \[(HCl,\text{ }ZnC{{l}_{2,}}or\text{ }N{{H}_{3}})\], resulting in the formation of a viscous liquid and after this, it does not allow any change in its property and act as heat and electricity resistor.

Complete Step by Step Solution:
Bakelite is not a rubber because rubber is termed an elastomer whereas bakelite is a thermosetting plastic. Rubber has the characteristic to be elastic and can be stretched whereas once Bakelite is prepared (set) on heating, it does not change its state and shape and is termed as rigid.

Rayon is a fibre whereas bakelite is a thermosetting plastic. Bakelite is set into any shape with some radiation or heat, it cannot be deformed easily upon further heating and thus is quite hard. This is not like fibres which are quite long, thinner than a strand of hair, and are not hard. Thus, bakelite is not a rayon.

Bakelite is a phenol-formaldehyde resin synthesised by the condensation reaction of phenol and formaldehyde. This process is multi-step, both phenol and formaldehyde are heated in presence of a catalyst which results in the formation of a condensation product (viscous liquid) soluble in alcohol and phenol. Then on further heating make it slightly soluble in alcohol. Continuing heating makes viscous liquid insoluble and hard material.

Whereas plasticizers are the substances that are usually added to the resin to promote elasticity, flexibility, and to make resin substances soften.
 Thus, the correct option is C.

Note: Bakelite resin is hard and resistant to heat and chemicals. Resins can be amorphous (viscous liquid) organic or inorganic solid. Resins are transparent or can be translucent. Condensation reactions involving phenol and formaldehyde are controlled to produce synthetic resin (resol).