Latest Biochemistry Interview Questions
1. What are the favorable conditions for formation of cat ions?
? Low Ionisational potential
? Lesser Charge
? More atomic size of atoms forms cations easily
? Ions having Inert gases configuration formed easily
2. What is electrophilic addition reaction?
When the attacking species during the addition reaction is Electrophile, it is called electrophilic addition reaction. Ex; (+) (-) (+) (-) (+) (-)
CH2Br-CH2BràH2C-CH2+BrBr-àH2C=CH2+Br2-
3. What is nucleophilic addition reaction?
When the attacking species during the addition reaction is Nucleophilic, it is nucleophilic addition reaction. Ex; Acetaldehyde cynohydrin
4. How do you define free radical addition reaction? Give an example.
When unsaturated compounds undergo addition reactions with free radicals,
it is called free radical addition reaction.
Ex; CH3-CH = CH2+HBr———–> CH3-CH2-CH2Br
5. What is addition reaction?
When atoms (or) group of atoms are added, to form more saturated compound it is called addition reaction.
6. Give the example for electrophilic substitution reaction.
The species, which accepts the electrons, are called Electrophilles (or) Electrophilic reagents.
When the atom (or) group of atoms present in the organic compound is replaced by another atom (or) group of atoms (electrophilic) is called electrophilic substitution reaction.
7. What are the favorable conditions for formation of Anions?
? High Electron affinity
? Small size
Less charge of an atoms form anion more easily
8. Define lattice energy.
The energy released when one mole of ionic crystal is formed by the combination of the corresponding gaseous (+ve) and (-ve) ions brought from infinite distance is called lattice energy.
9. What happens if Lattice energy increases?
? The Strength of ionic bond
? Stability of the Ionic compound
? Ease of formation of the Ionic bond Increases
10. What is Sublimation energy?
The amount of energy required to convert one mole of solid substance to vapor state is called Sublimation energy 11. What can you calculate by selecting Born-Haber cycle?
Born-Haber cycle is useful for calculation of lattice energy, heat of reaction and electron affinity.
12. How can energy change in the formation of NACL be determined?
With the help of Born Haber’s cycle
13. What is the relation between reaction taking place in one of the several stages and the total amount of energy liberated in the reaction?
The relation between reaction taking place in one of the several stages and the total amount of energy liberated in the reaction is same.
14. Define limiting radius.
The ratio between the radius of cation and the radius of anion is called Limiting radius.
15. What is Co-ordination number?
The number of appositively charged ions surrounded a particular ion in an ionic crystal lattice is called co- ordination number
16. What is structure of Nacl and give the co-ordination number of Nacl?
The structure of Nacl is face centered Cubic and Co- ordination number of Nacl is 6
17. What is the structure of cscl and give the co-ordination number of Cscl?
The structure of cscl is Body Centered Cubic and the Co- ordination number of CsCl is 8
18. Ionic compound does not show the property of space isomerism, Give the reason?
Ionic bond is Electrostatic. It is non directional, so Ionic compounds does not show the property of Space Isomerism
19. In double bond, how many sigma and Pi bonds are present in it?
Double bond = 1 Sigma bond and one Pi bond
20. Among sigma and Pi bonds which is the stronger one
Sigma bond is Stronger than pi bond
21. Define polar covalent bond
The covalent bond formed by the unequal sharing of electrons between the two atoms is called polar covalent bond.
22. What is dipole?
In polar covalent molecule, one atom gets positive charge and the other one gets negative charge hence called dipole.
23. Covalent bond is directional therefore which covalent property is shown?
Space Isomerism
24. Which theory explains the paramagnetic nature of oxygen? Who proposed it?
Molecular orbital theory, proposed by Hunds and Mulliken
25. Define co-ordination covalent bond.
Co-ordination covalent bond is formed by the mutual sharing of pair of electrons between two atoms contributed by only one of the combining atoms.
26. What does one Debye equals?
10-18 e.s.u – Cm
27. If a polar molecule has a charge of 4.8 * 10^ (-10) and internuclear distance is 1A then what is its dipole moment?
4.8 * 10-10 e.s.u * 1A0
4.8 * 10-10 * 10-8
4.8 * 10-18 e.s.u – Cm
= 4.8 Debye
28. Give the mathematical expression to calculate or measure the percentage of ionic Character.
% of Ionic Character = (Observed dipole moment / Dipole moment of 100% ionic bond)*100
29. Who proposed VSEPR theory? What does it explain?
VSEPR theory was proposed by Sedgwick and Powell. It explains the shapes of polyatomic molecules.
30. In water molecule the bond angle decreases from 109.28 to 104.5, why this does happens?
The repulsion between lone pair and lone pair electrons
31. In NH3 molecule, the bond angle decreases from 109.28 to 107.3 why does it happen.
The more repulsion between lone pair and bond pair
32. Define Hybridization.
The distribution of electrons into Hybrid orbitals is as per the Paulis Exclusion principle and the Hunds rule of Maximum Multiplicity.
33. According to which rule the distribution of electrons into hybrid orbital takes place.
The distribution of electrons into Hybrid orbitals is as per the Paulis Exclusion principle and the Hunds rule of Maximum Multiplicity.
34. What is the shape of molecules SF6 and IF7?
SF6 is Octahedral
IF7 is pentagonal Bipyramidal
35. Give the reason why the water molecule has high Boiling point and melting points.
Due to the presence of Hydrogen bond in water molecule
36. What are the units of bond length?
The intermolecular distance between the bonded atoms in a molecule is called bond length and the units are Angstrom units (A0)
37. What is the order of C-H bond length in C2H6 and C2H4 and C2H2?
c2h6>c2h4 >c2h2
38. Define bond angle.
The angle between the lines joining the nuclei of the bonded atom with a central atom is called bond angle.
39. IN XeF4, the bond angle between F-Xe-F is _________.
90 degrees
40. Define bond energy?
The amount of energy released when one mole of bonds are formed between the corresponding gaseous atoms is called Bond energy.
41. Define the phenomenon resonance?
When a molecule is represented by two or more nearly equal structures, which differ in the arrangement of electrons, then the molecule is said to exhibit resonance.
42. Which group of elements is called alkaline earth metals?
1st A group because the oxides and hydrides are alkaline in nature
43. Among 1A group elements why the element lithium is the most powerful, reducing agent in equivalent state
Due to its low sublimation and hydration energy
44. Among 1A group metals the lightest metal is
Lithium
45. Which metal is more metallic in nature among 1A group elements?
Francium
46. Which element in 1A group does not form peroxides?
Lithium
47. Which property among the following generally increases from top to bottom in a group 1A? 1. Electropositive, Density, Basic nature, classical reactivity
Electropositive, Density, Basic nature, classical reactivity, and solubility generally increase from top to bottom from lithium to caesium.
48. Which property among the following generally decreases from top to bottom in a group 1A? 1. Electropositive, Density, Basic nature, classical reactivity
Electro affinity, electro negativity, Ionisational potential, melting and boiling points decreases from top to bottom in a group 1A from lithium to caesium
49. Alkaline metals when dissolved in ammonium (NH3) act as better conductor and better reducing agent what is the reason behind it?
Due to formation of solvated or Ammoniated electrons
50. Which element in 1A group is lighter than water?
Lithium, Sodium, and potassium
51. In the extraction of sodium by cartners process the by-products formed are.
Hydrogen and Oxygen
52. In downs process sodium metal is extracted by the electrolysis of? In nelsons cell NaoH is prepared by electrolysis of.
Electrolysis of Brime solution
53. What are the raw materials used for the precipitation of Na2Co3 by Solvay ammonium Process?
Sodium Chloride, limestone and ammonia
54. Give the chemical formula for Borax.
(Na2) B4 (O7) .10(H2) O
55. Give the formula for Peral Ash.
The formula for Peral Ash is K2CO3.
56. What are the compounds used for extraction of Gold and Silver?
NaCN and KCN
57. Which is the most Abundant Alkaline earth element?
Calcium
58. Which is the least abundant Alkaline earth element?
Radium
59. What is the Chemical formula for Epsom salt?
MgSO4. 7H20
60. Why the 2A group elements are called Alkaline earth elements?
The elements occur in earth and the oxides of these metals are basic in nature hence the name alkaline earth metals.
61. Give the formula for baking soda.
The formula for baking soda is NaHCO3.
62. Dolomite is the ore of which element
Dolomite is an ore an element magnesium (mg)
Formula (MgCO3 CaCO3)
63. What is the name for magnesium per chlorate and what is its formula?
Magnesium per chlorate is called Anhydrone {mg (ClO4)2}
64. Bleaching powder is obtained when cl2 is passes through.
Dry Slake lime
CaOCl2+H2OàCa (OH) 2+Cl2
65. What is the ratio of slaked lime and sand in mortar?
Ratio is 1:3
66. Which elements are present in Electron?
Electron consist of 95 % mg, 5% Zn
67. Which are the most abundant metal and third abundant element in the earth crust?
Aluminium (Al) (7.28%)
68. What is inert pair effect?
The reluctances of ns electrons in the participation of bond formation is called inert pair effect
69. Name the family of third ‘A’ group elements
Boron family
70. In 3rd, name ‘A’ group elements which is the Non metal
Boron
71. Among third A group elements which element is best conductor?
Aluminium (Al)
72. Name the elements for which Cryolite and Pelspar are the ores.
Na3 Al F6àCryolite
K2O.Al2O3.6SiO2 (or) K Al Si3 O8àFelspar
Both are ores of Aluminium
73. What is the process, by which Aluminium is refined?
By Hoope’s process
74. Which process is used in welding the gaps in railway tracks?
Gold Schmidt’s alumino thermi process
75. What does Ammonal contain? For what purpose it is used.
It is a mixture of ammonium nitrate and aluminium powder is called ammonal, which is used as an explosive in Bombs.
76. What is Thermite mixture?
A mixture of Fe2O3 and ammonium powder in 3:1 ratio is called Thermite mixture.
77. What are hydrides of boron called?
Boranes
78. Which Univalent element cannot form Alums and why?
Lithium (Li+) does not produce alums because of its very small size.
79. How do we prepare Diborane?
The Diborane (B2H6) is prepared by the reduction of BCl3 with aluminium hydride
B2H6+3AlCl3+3LiClà4 BCl3+3LiAlH4
80. What is Banana bond? Diborane contains how many banana bonds
In Diborane B-H-B, bridge, which is formed by the sharing of two electrons, is called banana bond or Tau bond Diborane contains two banana bonds.
81. Give the formula of Borax. Borax is chemically called as.
Borax Na2B4O7 10H2O is chemically called as hydrated sodium tetra borate
82. Garnet is the ore of which element. Give its chemical formula.
Garnet is Silicate ore of Aluminium
(MgFe) 3 AlSi3O2.
83. How do you call fifth, ‘A’ group elements collectively?
Pnicogens
84. Name the family of fifth ‘A’ group elements.
Nitrogen Family
85. Which is the most reactive element in Nitrogen family?
Phosphorous
86. How much amount of energy is required to break the Triple bond in nitrogen molecule?
225 Kcal/mole or 945.4 KJ/mole
87. How many sigma and pi bonds are present in nitrogen formula?
Each nitrogen molecule contain one sigma and 2 Pi bonds
88. What are the important sources of Phosphorus?
Sources of Phosphorous are Phosphate rocks
? Flourapatite {2Ca3 (PO4)2 CaF2}
? Phosphorite {Ca3 (PO4)2}
89. Name two elements, which are Non-metallic in nature in 5th A group?
Nitrogen and Phosphorous
90. What is Allotropy?
Allotropy is Nitric acid
91. Negative oxidation states of nitrogen are because.
Higher Electro negativity
92. What is the molecular formula, Structure, and bond angle of Phosphorous?
P4- Phosphorous molecule (Tetra atomic)
Structure- Tetrahedral
Bond angle – (60 degrees
93. Allotrope form of phosphorous that conducts electricity is.
Black Phosphorous
94. More volatile and least volatile hydrides in 5thA group are.
PH3—more volatile
NH3—less volatile
95. What is the Anhydride of N2O5?
Nitric acid
96. Why nitrogen cannot form penta halides?
Because of the absence of d-orbital in its valency shells
97. Ortho Phosphoric acid is. Give oxidation no of phosphorous in it.
H3PO4-ortho phosphoric acid
Oxidation state of phosphorous is +5
98. What is the Super phosphate of lime?
Ca (H2Po4)2 caSO4. 2H2O. Super phosphate of lime is also called as Calcium super Phosphate
99. Sixth group elements are called as.
Chalcogens (ore forming elements)
100. What is the other name of sulphur?
Brimstone