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Multiple choice chemistry p- block elements-ii group 17 elements - general properties group 17 elements group 17 elements - properties

The electronic configuration of four atoms are given in brackets:
L : ($1s^2\,2s^2\,2p^1$);                    M : ($1s^2\,2s^2\,2p^5$);

Q : ($1s^2\,2s^2\,2p^6\,3s^1$);             R : ($1s^2\,2s^2\,2p^2$).

The element that would most readily form a diatomic molecule is :

  1. Q

  2. M

  3. R

  4. L
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

From the electronic configuration given it is clear that element M is 1 short of octet configuration. It belongs to group 17. Group 17 elements exist as diatomic molecules.


So, correct option is B.

Multiple choice chemistry p- block elements-ii group 17 elements - general properties group 17 elements group 17 elements - properties

Which is the correct arrangement of the compounds based on their bond strength?

  1. HF > HCl > HBr > HI

  2. HI>HBr>HCl>HF

  3. HCl>HF>HBr>HI

  4. HF>HBr>HCl>HI
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Because electronegativity decreases down the group thereby $e^-$ attracting tendency decreases down the group. $F$ with high electronegativity will have strongest bond and $I$ with least electronegativity will have least bond strength.

Multiple choice chemistry p- block elements-ii group 17 elements - general properties group 17 elements group 17 elements - properties

Mark the correct statements about halogens.

  1. Electron affinity of halogens is in the order F > Cl > Br > I.

  2. HF is the strongest hydrohalic acid.
  3. $F _{2}$ has lower bond dissociation energy than $Cl _{2}$.

  4. All halogens show variable oxidation states.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$F _2$ has lower bond dissociation energy than $Cl _2$ due to its small size and high electronegativity.

Multiple choice chemistry p- block elements-ii group 17 elements - general properties group 17 elements group 17 elements - properties

The property of halogens which is not correctly matched is:

  1. F>Cl>Br>I (Ionisation energy)

  2. F>Cl>Br>I (Electronegativity)

  3. I>Br>Cl>F (Density)

  4. F>Cl>Br>I (Electron affinity)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$e^-$ affinity of $F$ is less than that of $Cl$ because of the small size and high electronegativity of $F$ it repels the incoming $e^-$ thereby decreasing its $e^-$ affinity whereas $Cl$ having bigger size than $F$ & can accommodate the new incoming extra $e^-$.

Multiple choice chemistry p- block elements-ii group 17 elements - general properties group 17 elements group 17 elements - properties

Affinity for hydrogen decreases in the group from fluorine to iodine. Which of the halogen acids should have highest bond dissociation enthalpy? 

  1. $HF$
  2. $HCl$
  3. $HBr$
  4. $HI$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
As the size of the halogen atom decreases the bond length between halogen and hydrogen decreases ,So the bond becomes stronger and hence the energy required to break the bond ( bond dissociation enthaphy) increases.

So the compound with highest bond dissociation energy is $HF$

Hence option A is correct.
Multiple choice chemistry p- block elements-ii group 17 elements - general properties group 17 elements group 17 elements - properties

Match the column I with column II and mark the appropriate choice.

Column I Column II
(A) $H _{2}SO _{4}$ (i) Highest electron gain enthalpy
(B) $CCl _{3}NO _{2}$ (ii)Chalcogen
(C) $Cl _{2}$ (iii) Tear gas
(D) Sulphur (iv) Storage batteries
  1. (A) $\rightarrow$ (iv), (B) $\rightarrow$ (iii), (C) $\rightarrow$ (i), (D) $\rightarrow$ (ii)
  2. (A) $\rightarrow$ (iii), (B) $\rightarrow$ (iv), (C) $\rightarrow$ (i), (D) $\rightarrow$ (ii)
  3. (A) $\rightarrow$ (iv), (B) $\rightarrow$ (i), (C) $\rightarrow$ (ii), (D) $\rightarrow$ (iii)
  4. (A) $\rightarrow$ (ii), (B) $\rightarrow$ (i), (C) $\rightarrow$ (iii), (D) $\rightarrow$ (iv)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$H _2SO _4$ is used in storage batteries.

$CCl _3NO _2$ is chloropicrrin which is known as tear gas.
$Cl$ is the element of highest electron gain enthalpy.
Sulfur is the element belongs to 16th group which are also called as Chalcogens.
So the given data matches with option A.
Hence option A is correct.

Multiple choice chemistry p- block elements-ii group 17 elements - general properties group 17 elements group 17 elements - properties

Less ionic compound among the following

  1. NaF

  2. KCl

  3. KF

  4. NaCl
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

According to Fajan's rules, larger cations and smaller anions favor covalent character, while smaller cations and larger anions favor ionic character. Sodium chloride (NaCl) has a smaller anion compared to fluorides, making it relatively less ionic among the given alkali halides.