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Chemical Bonding and Molecular Structure

Long Answer Type

251.

Why does ice float over water?

276 Views

252.

Give reasons for the following:
(i) Density of water is maximum at 277K (4°C).
(ii) Why glycerol (glycerine) is more viscous than ethyl alcohol?

105 Views

Short Answer Type

253.

Explain the formation of a chemical bond.

240 Views

Long Answer Type

254.

Write Lewis symbols for the following atoms and ions:
S and S^2–; Al and Al³⁺; H and H^–.

494 Views

Short Answer Type

255.

Define octet rule. Write its significance and limitations.

1028 Views

256.

Write three favourable factors for formation of ionic bond.

166 Views

257.

Define bond length.

150 Views

Long Answer Type

258.
Explain the important aspects of resonance with reference to the $CO subscript 3 superscript 2 minus end superscript space ion. space$

In some molecules, single Lewis structure fails to explain all the characteristics of the molecules. As a result, a number of structure can be drawn to explain all the characteristics. Thus, such structure is called resonating structure.

In all C-O bonds are equivalent. This is possible only the different canonical structure of undergoing resonance to give resonance hybrid.