BTECH
COMPUTER SCIENCE
CHEMISTRY (BTCH101-23)
15 PRACTICE QUESTIONS WITH ANSWERS FOR EXAM
FROM FULL SYLLABUS
● ANSWERS:-
● Molecular Geometry and Hybridisation:
○ NH3: Trigonal pyramidal geometry, sp3 hybridisation.
○ XeF3: Square pyramidal geometry, sp3d hybridisation.
Fajan's Rule: States that a more polarizing cation leads to a greater covalent character
in the bond it forms with an anion.
● Effective Nuclear Charge: For Cobalt (Co) with atomic number 27, the effective
, nuclear charge (Zeff) calculations are provided for:
○ 3d electrons: Zeff = 6.9.
○ 4s electrons: Zeff = 3.9.
Ionization Enthalpy: Defined as the energy required to remove an electron from an
atom's valence shell. Noble gases have high ionization enthalpies because their valence
shells are full and stable.
● Hard Acids and Hard Bases:
○ Hard Acids: Small cations with high charge (e.g., Co3+, H+, Al3+).
○ Hard Bases: Small size with high charge (e.g., OH−, F−).
● PES Diagram for H3system: The document illustrates the PES (Potential Energy
Surface) diagram with a contour map for the H3system, noting that for a non-linear
molecule with N=3 atoms, there are 3 vibrational degrees of freedom (3N−6=3). The
spatial coordinates determining potential energy are described as the distance between
HAand HB, the distance between HCand the midpoint of the HA-HBbond, and the
angle between HCand the midpoint of the HA-HBbond.
●
●
COMPUTER SCIENCE
CHEMISTRY (BTCH101-23)
15 PRACTICE QUESTIONS WITH ANSWERS FOR EXAM
FROM FULL SYLLABUS
● ANSWERS:-
● Molecular Geometry and Hybridisation:
○ NH3: Trigonal pyramidal geometry, sp3 hybridisation.
○ XeF3: Square pyramidal geometry, sp3d hybridisation.
Fajan's Rule: States that a more polarizing cation leads to a greater covalent character
in the bond it forms with an anion.
● Effective Nuclear Charge: For Cobalt (Co) with atomic number 27, the effective
, nuclear charge (Zeff) calculations are provided for:
○ 3d electrons: Zeff = 6.9.
○ 4s electrons: Zeff = 3.9.
Ionization Enthalpy: Defined as the energy required to remove an electron from an
atom's valence shell. Noble gases have high ionization enthalpies because their valence
shells are full and stable.
● Hard Acids and Hard Bases:
○ Hard Acids: Small cations with high charge (e.g., Co3+, H+, Al3+).
○ Hard Bases: Small size with high charge (e.g., OH−, F−).
● PES Diagram for H3system: The document illustrates the PES (Potential Energy
Surface) diagram with a contour map for the H3system, noting that for a non-linear
molecule with N=3 atoms, there are 3 vibrational degrees of freedom (3N−6=3). The
spatial coordinates determining potential energy are described as the distance between
HAand HB, the distance between HCand the midpoint of the HA-HBbond, and the
angle between HCand the midpoint of the HA-HBbond.
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●
