This set of Pulp and Paper Multiple Choice Questions and Answers (MCQs) focuses on “Polymeric Additives”.
1. Paper making polymers can be categorized as naturally occurring polymers, modified naturally occurring polymers, and synthetic polymers.
a) True
b) False
View Answer
Explanation: They may also be classified as neutral, cationic, anionic or zwitterions. The widely utilized natural paper making polymers are polysaccharides or proteins.
2. The term _________is often utilized to mean a material containing cationic and anionic groups; strictly speaking, however, it means a material that is both acidic and basic.
a) Amphoteric
b) Zwitter ion
c) Neutral
d) Cationic
View Answer
Explanation: If compound is a molecule or ion that can react both as an acid and a base.HCO3– is amphoteric; it isn’t a zwitterion.
3. A molecule with only carboxylic acid is amphoteric and a zwitterion.
a) True
b) False
View Answer
Explanation: It is not strictly amphoteric, since the sulfonate is the conjugate base of a strong acid and not appreciably basic. A molecule with an amine and a sulfonate exists as a zwitterion.
4. Polymers with charged groups are called _________
a) Amphoteric
b) Zwitter ion
c) Neutral
d) Poly electrolytes
View Answer
Explanation: Anionic groups are usually carboxylates and occasionally sulfonates or phosphates. Cationic groups are usually amines or quaternary ammonium salts or quats.
5. A high charge density (above the 30% level) tends to completely unravel the normally coiled molecules in solution. What’s the criteria discussed here?
a) Poly electrolytes
b) Charge density
c) Zwitter ion
d) Amphoteric
View Answer
Explanation: The charge density calculated as the percentage of monomers containing a charge is an crucial criterion for polyelectrolytes. The electric charge / unit area of a surface, or / unit volume of a field or body.
6. _________ are relatively inexpensive polymers that are easily devised to high molecular weights on the order of several million (g/mol).
a) Poly electrolytes
b) Polyacrylamimdes
c) Charge density
d) Carboxylate
View Answer
Explanation: It is a polymer (-CH2CHCONH2-) which are formed from acrylamide subunits. It could be formed as a simple linear-chain structure or cross-linked.
7. Anionic _________ usually contains about 5% polyacrylic acid groups formed by co-polymerization of acrylamide and acrylic acid monomers or by hydrolysis of P.A.M. homopolymer under conditions to convert some of the amide groups to carboxylate salts.
a) Poly electrolytes
b) Polyacrylamimdes
c) Charge density
d) Carboxylate
View Answer
Explanation: Polyacrylamide could be supplied in a powder or liquid form, with the liquid form being subcategorized as solution and emulsion polymer. This process applies to water treatment, and processes like paper making and screen printing.
8. Potato _________ has about 0.1 to 0.3% equivalent PO4 corresponding to a degree of substitution of 0.002 to 0.005.
a) Starch
b) Lignin
c) Pulp
d) Protein
View Answer
Explanation: Potato starch has little protein, while corn starch is about 0.3% protein. These granules and the starch therein are made soluble by the cooking process. Starch is a polymeric carbohydrate which consists a large number of glucose units which are joined by glycosidic bonds.
9. _________ reactions of secondary and primary amines are analogous where 1 or 2, respectively, of the R groups are protons.
a) Acid dissociation
b) Base dissociation
c) Cationic association
d) Anionic association
View Answer
Explanation: An acid dissociation constant, Ka is also known as acidity constant. It is a quantitative measure of the strength of an acid in the solution. Protonated trimethylamine has a pKa of 9.80 and triethylamine has a pKa, of 10.72.
10. _________ serves as a model compound for the acid ionization behaviour of many carboxylic acid groups.
a) Hydroxylic acid
b) Sulphuric acid
c) Acetic acid
d) Nitric acid
View Answer
Explanation: It has a distinctive sour taste and pungent smell. It’s classified as a weak acid, concentration acetic acid is corrosive and can attack the skin.
Sanfoundry Global Education & Learning Series – Pulp and Paper.
To practice all areas of Pulp and Paper, here is complete set of 1000+ Multiple Choice Questions and Answers.