Identify the non-polar molecule in the set of compounds given :

HCl, HF, H₂, HBr

• H₂

• HCl

• HF, HBr

• HBr

Which of the following pairs involves isoelectronic ions ?

• Mn³⁺ and Fe²⁺

• Mn²⁺ and Fe³⁺

• Cr³⁺ and Mn²⁺

• Fe²⁺ and Co²⁺

Which one of the following has the highest electronegativity ?

• Br

• Cl

• P

• Si

The only non-metal which is liquid at ordinary temperature is :

• Hg

• Br₂

• NH₃

• None of these

Which is the correct order of electronegativity?

• F > N < O < C

• F > N > O > C

• F > N > O < C

• F < N < O = C

Which of the following is amphoteric ?

• V₂O₃

• CuO

• V₂O₅

• NiO

The solubilities of carbonates decrease down the magnesium group due to a decrease in

• lattice energies of solids

• hydration energies of cations

• inter-ionic attraction

• entropy of solution formation

Due to the presence of an unpaired electron free radicals are

• cations

• anions

• chemically inactive

• chemically reactive

Ionic radii are

• inversely proportional to effective nuclear charge

• inversely proportional to square of effective nuclear charge

• directly proportional to effective nuclear charge

• directly proportional to square of effective nuclear charge

160.

Which one of the following arrangements represents the correct order of electron gain enthalpy (with negative sign) of the given atomic species ?

• Cl < F < S < O

• O < S < F < Cl

• S < O < Cl < F

• F < Cl < O < S