Question | Answer |
Electronic Theory of Valency explains the electronic
structure of the elements, Inert gases like neon,
argon, krypton do not exhibit valency. The valency of
inert gases, is | Zero |
Electrically charged atoms/groups of atoms are
balled ‘ions’ cations are positively charged ions, (e.g.,
Na+, Mg++ , etc.) Cl–, O2–, etc, are negatively charged
ions. These are known as | Anions |
Ionic bond is formed by the electron transfer from
one atom to another among the atoms. NaCl is an ionic
bond. Covalent bond forms by the sharing of electrons,
(e.g., CO2 electrons). Shape of CO2 molecule is | Colinear |
Ammonia has pyramidal shape and water molecule
is angular in shape. Which type of. bonds are
present in NaOH, HCN and H2SO4? | Both Ionic and Covalent Bond |
Covalent bonds are of two types depending upon
the types of overlapping of orbitals—Sigma () bond
and Pi () bond. Who introduced the concept of
hybridisation? | Pauling |
BeCl2 has | sp hybridisation |
, BCl3 has | sp2
hybridisation |
. The hybridisation in PCl5 is | sp3d |
Heitler and London (1927) introduced | the Valence Bond Theory (VBT). It is based on the knowledge of atomic orbitals and electronic configuration of the elements. |
Molecular Orbital Theory (MOT)
was developed by | F. Hund and RS Mulliken (1932) |
Molecule Shape SiCl4 | Tetrahedral |
Molecule Shape AsF5 | Trigonal bipyramidal |
Molecule Shape H2S | Bent/V-shaped |
Molecule Shape PH3 | Trigonal bipyramidal |
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