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Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

Which of the following can be hydrolysed?

  1. $TeF _6$
  2. $NCl _3$
  3. $SF _6$
  4. Both $1$ & $2$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$TeF _6$ canbe easily hydrolysed because of large size of Te central atom and low electronegativity the bond polarity of this bond is more .so, it is more reactive than other compounds like $SF _6$

$TeF _6+6H _2O\longrightarrow H _6TeO _6+6HF$

Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

Which of the following is least stable?

  1. $Tl{I} _{3}$
  2. $Tl{F} _{3}$
  3. $Pb{F} _{4}$
  4. $Pb{I} _{4}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

PbI4 is the least stable because Pb(IV) is a strong oxidizing agent and I- is a strong reducing agent, leading to spontaneous reduction to Pb(II) and I2. In contrast, fluorides are more stable because fluorine is a poor reducing agent.

Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

$PbI _4$ does not exist because :

  1. iodine is not a reactive
  2. $Pb(IV)$ is oxidizing and $I^-$ is strong reducing agent
  3. $Pb(IV)$ is less stable than $Pb(II)$
  4. $Pb^{4+}$ is not easily formed
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

PbI4 does not exist because the Pb(IV) state is unstable relative to Pb(II) in the presence of a strong reducing agent like iodide. The energy released by the reduction of Pb(IV) to Pb(II) is greater than the energy required to form the Pb-I bonds.

Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

Halogens have:

  1. high ionisation energies

  2. high electronegativities

  3. high electron affinities

  4. All the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Halogens have high ionisation energies, high electronegativities and high electron affilities due to their smallest size in a particular period. As size decreases ionisation energy, elctronegativity and electron affinity increaes

Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

_______ is the only member of the halogen family that has no stable isotopes.

  1. $\displaystyle F$
  2. $\displaystyle Cl$
  3. $\displaystyle Br$
  4. $\displaystyle I$
  5. $\displaystyle At$
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Astatine has many isotopes, all of which are radioactive in nature. Their half-lives are also very small. Hence, astatine has no stable isotopes.

Option $E$ is the correct answer.