${\mathrm{S}}_2{\mathrm{O}}_8^{2-}$ have

• S-S bond

• S-O bridge

• O-O bridge

• All S-O bond lengths are same.

N-N bond length is minimum in

• N₂O

• N₂O₃

• N₂O₄

• N₂O₅

Assertion : Diamond and graphite do not have the same crystal structure.

Reason : Diamond is crystalline while graphite is amorphous.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : Bohr model fails in case of multielectron pecies.

Reason : It does not mention electron-electron interactions.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : ClF₃ has T-shape structure.

Reason : It has two lone pairs arranged at 180° angle.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false

Assertion : O₂ is paramagnetic.

Reason : It has one unpaired electron.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : In a pressure cooker, the water is brought to boil. The cooker is then removed from the stove. Now on removing the lid of pressure cooker, the water starts boiling again.

Reason: The impurities in water bring down its boiling point.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

For silicon which is not correct?

• It is a type of silicate.

• It is thermally unstable.

• It is hydrophilic.

• Repeating unit is R₂SiO.

If Si is doped with B,

• n-type semiconductor is formed

• p-type semiconductor is formed

• insulator is formed

• polymer is formed.

20.

Living in the atmosphere of CO is dangerous, because it

• combines with O, present inside to form CO₂

• reduces organic matter of tissues

• combines with haemoglobin and makes it incapable to absorb oxygen

• dries up the blood.