s and p-Block Elements

Which ion has the maximum degree of hydration among alkali metals?

Cs+
Li+ (correct)
Rb+
K+

What is the correct order of electronegativity of alkali metals from highest to lowest?

Li > Na > K > Rb > Cs
Na > Li > K > Rb > Cs
Cs > Rb > K > Na > Li
Li < Na < K < Rb < Cs (correct)

Which ion has the highest conduction power among alkali metals?

Cs+ (correct)
Li+
Na+
K+

What is the correct order of relative hydrated ionic radii of alkali metals?

Li+ < Na+ < K+ < Rb+ < Cs+ (C) Signup and view all the answers

Which of the following statements is true about alkali metals?

Metallic character and electro positivity increase from Li to Cs (C) Signup and view all the answers

What is the primary reason for the higher values of heat of hydration for divalent cations of alkaline earth metals?

Their tendency to form stable compounds with high lattice energy (A) Signup and view all the answers

Which of the following alkaline earth metals has the highest standard oxidation potential?

Be (C) Signup and view all the answers

What is the characteristic of the oxides formed by Ba and Ra when burnt in air?

Peroxide in nature (D) Signup and view all the answers

What is the trend in the hydration energies of M ions with increase in ionic radii?

Decreases (A) Signup and view all the answers

Which of the following alkaline earth metals is not a powerful reducing agent?

Be (D) Signup and view all the answers

What is the primary reason why the alkali metal salts are colourless and diamagnetic?

Because of their ns configuration with no unpaired electrons (D) Signup and view all the answers

What is the correct order of increasing atomic radius of alkali metals?

Li < Na < K < Rb < Cs < Fr (B) Signup and view all the answers

What is the correct statement about the hydration of alkali metal ions?

Smaller the cation, greater is the degree of hydration (A) Signup and view all the answers

What is the correct explanation for the lustre of freshly cut alkali metals?

Due to the surface oxidation of the metal (A) Signup and view all the answers

What is the correct expression for the hydration energy of an alkali metal ion?

M (g) → M+ (aq) ; ΔH = -ve (A) Signup and view all the answers

What is the trend in the density of alkali metals down the group?

It increases gradually (B) Signup and view all the answers

Why is potassium lighter than sodium despite being below it in the periodic table?

Due to its unusually large atomic size (D) Signup and view all the answers

What is the crystal lattice structure of alkali metals in their solid state?

Body-centred cubic lattice (D) Signup and view all the answers

What is the reason for the low melting and boiling points of alkali metals compared to other group members?

Due to their low ionisation energy values (D) Signup and view all the answers

Why do alkali metals exhibit strong electropositive character?

Due to their low ionisation energy values (B) Signup and view all the answers

What is the primary reason for the anomalous behavior of boron trifluoride, regarding its Lewis acid character?

The fluorine atom's tendency to back-donate its unutilised electrons to the vacant p orbitals of boron atom. (B) Signup and view all the answers

Which of the following boron trihalides has the highest Lewis acid character?

BI (B) Signup and view all the answers

What is the reason behind the efficient Lewis acid nature of boron halides?

Their ability to accept a pair of electrons from a donor molecule to complete their octet. (B) Signup and view all the answers

Which of the following metals exhibits a characteristic similar to Al and Ga in terms of forming a protective film of oxides?

Thallium in HCl (A) Signup and view all the answers

What is the primary use of BF3 due to its Lewis acid nature?

As a catalyst in organic reactions. (B) Signup and view all the answers

What is the reason why alkaline earth metals form divalent ions instead of univalent ions?

Due to the higher degree of hydration of their divalent ions (D) Signup and view all the answers

What is the effect of hydration on the energy of alkaline earth metal ions?

It decreases the energy of the ion (D) Signup and view all the answers

Why do alkaline earth metals tend to exist as divalent cations in solution?

Due to the strong lattice structure of their divalent ions (A) Signup and view all the answers

What is the reason why alkaline earth metals do not form univalent ions despite having low ionisation energy?

Due to the higher degree of hydration of their divalent ions (A) Signup and view all the answers

What is the benefit of hydration in the formation of divalent ions of alkaline earth metals?

It compensates for the higher value of second ionisation energy (B) Signup and view all the answers