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Question: 1
What are epoxy resins?
Answer: 1
1-47The epoxy resin are fundamentally polymers but retain their name on the basic of the starting material and the presence of epoxide group in the poly,er.The epoxy resin is made by condensing epichlorohydrin with diphenylol propane.
Question: 2
What are polymers?Give two example.
Answer: 2
2-47Polymers are describe as large molecule built up from small repeating units.called monomers,The word polymers is derived from greek,poly mean many and mer mean parts.
For example: Cotton,wood,plastics.
Question: 3
Define polymerization,Explain polymerization reaction of ACetylene.
Answer: 3
3-47Formation of polymer from its respective monomers at standard condition is called polymerization.When acetylene is passed through a copper at 300 C ,it polymerizes to benzene,
Question: 4
Give the classification of polymer?
Answer: 4
4-47IN 1929,W.H Carothers suggested a classification of the polymerization process into two depending upon the way the polymer are formed.
Addition Polymerization:It is free radical addition reaction which involves initiate,propagation and termination steps.For example polymerization of styrene.
Condensation polymerization: The polymerization results from the mutual reaction of two functional groups ,This reaction usually involves the removal of a water molecule or a methanol molecule,It take place at the both end of the growing chain.
Question: 5
What are macromolecules?
Answer: 5
5-47Macromolecules or polymers are described as larger molecule built up from small repeating units called monomers.
For example: Wool,Cotton,PVC
Question: 6
What are thermoplastics and thermosetting polymers?
Answer: 6
6-47Thermoplastics polymer: A thermoplastic polymer is one which can softened repeatedly when heated and hardened when cooled with a little change in properties. For example PVC pipes,plastics toys etc.
Thermosetting polymers:The polymer which becomes hard on heating and can not be softened again are called thermosetting polymers,A thermosetting polymers on heating decompose instead of melting For example synthetic ,varnish ,epoxy resins etc.
Question: 7
What is the degree of polymerization?
Answer: 7
7-47The length of polymer chain is specialized by the number of repeating units in the chain is known as degree of polymerization.
Question: 8
How the degree of polymerization helps to determine the molar mass of the polymer?
Answer: 8
8-47The molecular mass of the polymer is the product of the molecular mass of the repeating unit and the degree of polymerization ,For example,polyvinyl chloride, a polymer of degree of polymerization 1000,has molecular mass,
Question: 9
What is copolymer?
Answer: 9
9-47Copolymer is formed by the polymerization of two monomers together e,g vinyl acetate reacts with butyl maleate to give a copolymer.
Question: 10
Define condensation polymerization.
Answer: 10
10-47The polymerization results from the mutual reaction of two functional groups .The reaction usually involves the removal of a water molecule or methanol molecule,It take place at both end of the growing chain.
Question: 11
What is addition polymerization?
Answer: 11
11-47It is free radical addition reaction which involves initiation,propagation and termination steps,For example polymerization of styrene,Addition of polymerization is catalyst by thermal or photochemical decomposition of organic peroxides to give free radials.
Question: 12
Classify polymer on the basic of monomers?
Answer: 12
12-47Homopolymer:A homopolymer is formed by the polymerization of a single type or monomer.
Copolymer : A copolymer is formed by the polymerization of two monomer together e.g vinyl acetate reacts with butyl maleate to give a copolymer..
Question: 13
Briefly describe the simple protein?
Answer: 13
13-47These protein on hydrolysis yield only amino yield acids or their derivatives,For example albumins,globulins,legumin collagen etc,globulins are insoluble in water but soluble in dilute salt solution ,They are found in animals,is also found in muscles and also in plants,
Question: 14
How polystyrene is prepared?
Answer: 14
14-47Polystyrene is used in the manufacturing of floor containers cosmetic ,bottles toys and packing material etc.
Question: 15
What is the difference glucose and fructose?
Answer: 15
15-47Glucose : Consists of aldehyde group and also called dextrose ,grape sugar or blood sugar ,occur naturally in both combines and free state ,Ib the free state it is present in most sweet fruits and in honey,Small quantity of glucose and also present in human blood and urine.
Fructose: consists of ketone group and is also found in combined and free states,It is used as a sweetening agent in confectionery and as substitute of cane sugar,
Question: 16
Give the classification of carbohydrates along with an example?
Answer: 16
16-471.Monosaccharides:
For example : glucose ,fructose ,glactose
2.Disaccharides or Oligosaccharises:
For example: Sucrose,lactose ,maltose
Question: 17
Write importance of epoxy resin?
Answer: 17
17-47The major used of epoxy resin is in coating material which gives toughness flexibility adhesion and chemical resistance,Industrial material thermal power station packing material are coated with epoxy paints.Dams bridges ,floor etc are painted with epoxy resins.
Question: 18
What are polyamide resin?
Answer: 18
18-47These resingsara formed by the condensation of polymenies with adipic dicarboxylic acid.One of the most famous condensation polymers discovered it Nylon.
Question: 19
How Nylon 6,6 can be obtained?
Answer: 19
19-47Nylon 6,6 is obtained by heating adipic acid with hexamethylenediamine.Nylon 6,6 derives its name from its starting materials adipic acid and hexamethylenediamine,both of which have six carbons atoms.
Question: 20
Write use of polystyrene.
Answer: 20
20-47It is used in the manufacturing of goof container ,cosmetics bottles ,toys and packing material etc.
Question: 21
What is PVC ?
Answer: 21
21-47It is addition polymer obtained by polymerizing vinyl chloride at 52 Degree or 9 atmospheric pressure.
Question: 22
Define monosaccharides.
Answer: 22
22-47The carbohydrate having empirical formula where n=3 or some larger number are called monosaccharides.Monosaccharide are either aldoses or ketoses.Common example are glyceraldehyde,glucose fructose etc,
Question: 23
What is Glycogen?
Answer: 23
23-47It occurs mainly on the liver and muscle where it represent the main storage polysaccharide in the same way as starch function in planet cells,Glycogen is therefore also called animal starch,Its structure closely resembles with that of amylopectin have 1-4 and 1-6 glycosidic linkage.
Question: 24
How PVC is prepared?
Answer: 24
24-47It is an addition polymer obtained by polymerizing vinyl chloride at 52 Degree and 9 atmospheric pressure.
Question: 25
What is Rancidity of fats or oils?
Answer: 25
25-47Fats or oils are liable to spoilage and give off an odour known as rancidity,It is mainly caused by the hydrolytic or oxidation reaction which release foul smelling aldehydes and fatty acids,
Question: 26
Name different types of proteins on the basis of physcio-chemical properties.
Answer: 26
26-47Based on physical chemical proteins ,proteins may be classified into three types.
- Simple proteins
- Compounds or conjugated proteins
- Derived proteins
Question: 27
Give two differences between Oil and fats?
Answer: 27
27-471.Oil are unsaturated and fats are saturated compounds,.Unsaturated glycerides reacts with hydrogen in the presence of metal catalyst to give saturated glycerides,The result is the conversion of liquid glyceride into semi solid glyceride.
2.Oils have low melting points and fats have high melting points.
Question: 28
What happens when the hydrolysis of triglyceride is carried out?
Answer: 28
28-47Triesters are easily hydrolysed by enzymes called lipases to fatty acids and glycerol.
Question: 29
What are derived proteins?
Answer: 29
29-47They are the hydrolytic products of the above mentioned compounds,Sterols vitamin D and terpenes belong to this class of lipids.
Question: 30
What is triglycerides?
Answer: 30
30-47A triester of glycerol is called a triglycerides or glyceride.
Question: 31
List 2 important use of proteins.
Answer: 31
31-471.Proteins take essential part in the formation of protoplasm which is the essence of all form of life.
2.Enzymes which are biological catalyst are protein in the nature ,Without them life in not possible.
Question: 32
Explain denaturation of protein?
Answer: 32
32-47The structure of protein can be disrupted easily by heat,change in pH and under strongly oxidizing or reducing condition,Under such conditions the proteins undergo denaturation,The most familiar example of denaturation is the change that take place in albumin,the principle component of egg,white when it is cooked in,In this particular case the change is irreversible.
Question: 33
Write down the physical properties of Lipids.
Answer: 33
33-471.Lipids are insoluble in water and soluble in non-polar solvents e.g ether,chloroform and benzene etc.
2.Their primary building bock are fatty acids glycerol and sterol.
3.Lipids are utilized by the living organisms.
Question: 34
How polystyrene is prepared,.
Answer: 34
34-47Polystyrene is prepared by the polymerization of styrene in the presence of a catalyst.
Question: 35
What is meant by saponification number?
Answer: 35
35-47It is defined as the number of milligrams of potassium hydroxide or sodium hydroxide require to saponify one gram o of tha fat or oil.
Example One mole of glycerol tripalmitate require 168.000 mg of KOH for saponification,Therefore one gram of fat will require 168000/807 mg of KOH.Hence the saponification number of glycerol tripalmitate is 208.
Question: 36
Define lipids.
Answer: 36
36-47Lipids are naturally occurring organic compounds of animals and plants origin which are soluble in organic solvents and belong to a very heterogeneous group of substance.
Question: 37
Write any difference between DNA and RNA?
Answer: 37
37-471.The sugar in RNA is ribose while the sugar in DNA is 2-deoxyribose.
2.Four different bases are found in DNA cytosine,thymine,adenine and guanine.In RNA thymine does not occur and its place u taken by uracil .
Question: 38
Write the factor which affect the enzyme activity?
Answer: 38
38-47- Enzymes concentration
- Effect of pH
- Radiation
- Temperature
- Coenzymes,activators and inhibitors.
Question: 39
What is chemical nature of enzyme?Classify them.
Answer: 39
39-47Enzymes are either pure proteins or contain proteins as essential components and in addition require non protein component which are essential for their activity,The protein components of the enzyme is called apoenzyme and the non protein component is called co factor or co factor or co enzyme the cofactor include inorganic ions and complex organic metallo organic molecules.
Question: 40
Define acid number.
Answer: 40
40-47The acid number of a fat or an oil tells the amount of free fatty acids present in it,It is expressed as the number of milligrams f potassium hydroxide required to neutralize one gram of fat,
Question: 41
Define Enzymes ,name their two properties?
Answer: 41
41-47The reaction catalyst of biological systems produced by living cells and are capable of catalyzing chemical reaction are called enzymes.
Properties of enzymes:
1.Enzymes are protein or contain proteins as essential components and in addition require non protein components which are also essential for their activity.
2.Many enzymes contain vitamins as their co factors for example ,nicotinamide adenine dinucleotide contain nicotinamide vitamin.
Question: 42
Write a note on Cholesterol?
Answer: 42
42-47It is the most abundant animal sterol occur in all animals tissues but it is only in a few higher plants,Cholesterol is present both in the free as well as esterified from in the blood,animals tissues ,egg an yolk,various and fatd and nerve tissue.
Question: 43
Write down important use of lipids?
Answer: 43
43-47- Lipids are good source of energy and make the food more palatable.
- Lipids exert an insulting effect on the nervous tissues,.
- Lipids are good energy reservoirs in the bofy,
Question: 44
Discuss effect of temperature and pH on enzyme activity?
Answer: 44
44-47The enzymatic reaction occurs best at or around 37 Degree which is the average normal body temperature,The rate of chemical reaction is increased by a rise in temperature but this is only over a limit range of temperature,The enzymes usually destroyed at high temperature,the activity of enzyme is reduced at low temperature.The temperature at which an enzyme reaction occurs the fastest is called it optimum temperature.
Question: 45
What are the following
1.Isoenzyme
2.Nucleotide
Answer: 45
45-47Isoenzyme:These are the enzymes from the same organisms which catalyze same reaction but are chemically and physically distinct from each other.
Nucleotide:Both DNA and RNA are formed by joining together a large number of Nucleotide units ,each of which is a nitrogenous base sugar phosphoric acid complex.
Question: 46
What are steroids?
Answer: 46
46-47Steroids are naturally occurring lipids.Their parent nucleus has per hydri cyclopentanophenanthrene component which consists of three six members rings and one five membered ring these rings are joined or fused to each other an have a total of 17-C atoms,
Question: 47
What are nucleosides and nucleotides?
Answer: 47
47-47Nucleosides : A nucleosidesus a combination of nitrogenous base with a sugar ,Depending upon the presence of ribo or deoxyribo ,nucleoside can either be a ribonucleoside or deoxyribonucleoside.
Nucleotides:Nucleotides are the organic molecule that serve as the monomer units for forming the nuclei acid polymer DNA or RNA,DNA carries the genetic information and RNA is involve inputting this information to work in the cell.
