21.

Which of the following is a favourable factor for cation formation ?

• Low ionisation potential

• High electron affinity

• High electronegativity

• Small atomic size

Which of the following statements is not an essential feature of an optically active molecule ?

• It will rotate the plane of polarised light

• It will have a non-superimposable mirror image

• It will have no element of symmetry

• It will have an asymmetric carbon atom

Which one of the following is the most stable reactive intermediate?

The reagent which could distinguish between 1-hexyne and 1-hexene is :

• Ag$({\mathrm{NH}}_3{)}_2^{+}$

• KMnO₄

• Br₂ in CCl₄

• H₂SO₄

Choose the correct reagent required to carry out the transformation :

• Zn + conc. HCl

• conc. H₂SO₄

• Li then H₂O

• H₂/Pt

Which is maximum hydrated ?

• NaCl

• MgCl₂

• AlCl₃

• SiCl₄

Ozone layer is being depleted. This is due to :

• NO (nitric oxide) emission from supersonic jets

• chlorofluoro carbon used as aerosols

• Both (a) and (b)

• None of the above

Arrange the following compounds in increasing order of rate of reaction towards nucleophilic substitution :

• I < II < III

• I < III < II

• III < II < I

• II < III < I

Which can dissolve I₂ ?

• KI

• NaI

• LiI

• HI

The oxygen carrying pigment , oxyhaemocyanin containing two copper ions is diamagnetic , because :

• the two copper ions are in + 1oxidation state

• one copper ion is in + 1oxidation state while other is in + 2 oxidation state

• of the strong antiferromagnetic interactions between two copper ions

• of the ferromagnetic interactions between the two copper ions