Description : Define polymerization. Explain addition polymerization with at least one example.
Last Answer : Polymerization: - The process in which a large number of small molecules (monomers) linking together to form a large molecule (polymer) under specific conditions of temperature, pressure & catalyst is ... catalyst. iv) No byproduct is obtained. v) It yields polymer having linear chain structure.
Description : Write the properties and applications of thermocole.
Last Answer : Properties :- i) It is soft, spongy, porous, low density. ii) Its thermal & electrical conductivity is low. iii) It is quite shock - proof. iv) It is quite strong through extremely light. ... used for storing ice, ice creams & medicines. 7) It is used as a float for swimming.
Description : Name and describe the process which increases the stiffness of rubber.
Last Answer : Name: Vulcanization process is used to increase stiffness of rubber. Explanation: The process which involves addition of Sulphur or H2S to crude (raw) natural rubber at high temperature and ... in the rubber molecule of different rubber springs. Chemical reaction (Mechanism):
Description : Describe with labeled diagram the process of electroplating of silver.
Last Answer : 1. Electroplating of silver on iron - spoon is carried out in a rectangular steel tank. 2. Iron spoon, which is to be electroplated, is cleaned by boiling with caustic soda in order ... spoon gets plated with silver. Silver anode gets slowly dissolve in solution by giving Ag+ ions.
Description : Define : i) Atomic number ii) Atomic mass number iii) Energy level iv) Sub energy level
Last Answer : i) Atomic number: It is defined as; the number of protons present in the nucleus, which exactly balances the number of electrons present in the extra nuclear part. ii) Atomic mass number: It ... : The close grouping of number of energy levels in the main energy level is called sub energy level.
Description : Write drawback of natural rubber.
Last Answer : Drawbacks of natural rubber: 1. It has low tensile strength. 2. It is too weak to be used in heavy duty operation. 3. During summer, the raw rubber becomes soft and sticky, while ... It gets tarnished in air due to oxidation. As a result, its durability is considerably by vulcanization.
Description : Write composition of Wood’s metal.
Last Answer : Composition:- Bi=50% Pb = 25% Sn = 12.5% Cd = 12.5%
Description : Define concentration of ore. Name different methods of concentration.
Last Answer : Concentration of ore: The concentration of ore means the removal of gangue or matrix from crushed ore. Methods: i) Gravity separation ii) Electromagnetic separation iii) Froth floatation iv) Calcination v) Roasting
Description : Define the terms 1) Flux 2) Slag.
Last Answer : Flux: ‘A substance which is used to remove the gangue from ore is called flux’. Slag: A fusible chemical compound formed by combination of the added flux and the gangue present in the ore.
Description : Postulates of Arrhenius theory of ionization.
Last Answer : 1. The molecules of an electrolyte when dissolved in water split up into two kinds of charged particles, positively charged particle known as cation, negatively charged particle known as anion. 2. ... anions corresponds to the valency of the element or radical from which the ion is derived.