Draw diagrams showing the formation of a double bond and a triple bond between carbon atoms in C2H4 and C2H2 molecules.
C2H4 :
The electronic configuration of C-atom in the excited state is:
C has 4 unpaired electrons in the valence shell,therefore in the formation of C2H4 , each Carbon atom undergoes sp2 hybridization leaving 2pz orbital unhybridized.
One sp2 hybrid orbital of one carbon overlaps with sp2 hybrid orbital of other carbon atom to form sigma c---c bond.Now the unhybridized 2pz orbital of one carbon atom overlaps sidewise with similar orbital of the other carbon atom to form pie bond.The remaining 2 sp2 hybrid orbitals of both carbon atoms overlap axially with the half filled 1s orbitals of hydrogen atom forming C---H sigma bond
ORBITAL STRUCTURE OF C2H4
C2H2 :
Here both the carbon atoms undergoes sp hybridization leaving 2 unhybridized (2py & 2pz) orbitals.One sp hybrid orbital of one carbon atom overlaps axially with sp hybrid orbital of other carbon forming C----C sigma bond. The two unhybridised orbital of one carbon overlaps sidewise with similar orbital of other carbon atom to form two pie bonds. The remaining hybrid orbitals of each carbon overlaps axially with half filled orbitals of Hydrogen forming sigma bond.
ORBITAL PICTURE OF C2H2
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Use molecular orbital theory to explain why the Be2 molecule does not exist.
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O2,O2+,O2- (superoxide), O22-(peroxide)
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BeCl2, BCl3, SiCl4, AsF5, H2S, PH3
Explain why BeH2 molecule has a zero dipole moment although the Be–H bonds are polar.
Write Lewis symbols for the following atoms and ions:
S and S2–; Al and Al3+; H and H–
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(i) CH2=C=O,
(ii) CH3CH=CH2,
(iii) (CH3)2CO,
(iv) CH2=CHCN,
(v) C6H6
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Calculate the molecular mass of the following:
(i) H2O
(ii) CO2
(iii) CH4
Assign oxidation number to the underlined elements in each of the following species:
(a) NaH2PO4
(b) NaHSO4
(c) H4P2O7
(d) K2MnO4
(e) CaO2
(f) NaBH4
(g) H2S2O7
(h) KAl(SO4)2.12 H2O
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(i) used to determine heat changes
(ii) whose value is independent of path
(iii) used to determine pressure volume work
(iv) whose value depends on temperature only.
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a) What is the initial effect of the change on vapour pressure?
b) How do rates of evaporation and condensation change initially?
c) What happens when equilibrium is restored finally and what will be the final vapour pressure?
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List gases which are responsible for greenhouse effect.
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(a) Na (b) K (c) Rb (d) Cs
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Explain why alkali and alkaline earth metals cannot be obtained by chemical reduction methods?
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XeO4– 6(aq) + 2F – (aq) + 6H + (aq) → XeO3(g) + F2(g) + 3H2O(l)
What conclusion about the compound Na4XeO6 (of which XeO4– 6 is a part) can be drawn from the reaction.
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Thanks for overall explanation ð
Draw the orbital picture of CH4
Gud
Plz show only double bond and triple bond not rhe orbital structure
Bakwass