Tag: group 17 elements - properties

Questions Related to group 17 elements - properties

In NaOX , X cannot be

  1. ${ F } _{ 2 }$

  2. ${ Cl } _{ 2 }$

  3. ${ Br } _{ 2 }$

  4. $I _{ 2 }$


Correct Option: D

The strongest oxidising agent is :

  1. ${ Cl }^{ -1 }$

  2. ${ F }^{ -1 }$

  3. $O^{ -2 }$

  4. $N^{ -3 }$


Correct Option: B

The table shows some information about elements in Group VII of the Periodic Table. 

Name State at room temperature Colour
Chlorine Gas yellow-green
Bromine liquid brown
iodine ? ?
Astaine solid black

Which information about iodine completes the table?

  1. State - liquid, colour - black

  2. State - liquid, colour - green

  3. State - solid, colour - grey

  4. State - solid, colour - yellow


Correct Option: D
Explanation:
$\text{D) State-solid,Colour-yellow}$
$\text{Iodine is solid at room temperature and appears yellow in low concentrat}$

Affinity for hydrogen is maximum for

  1. $\mathrm{F} _{2}$

  2. $ \mathrm{Cl} _{2}$

  3. $\mathrm{B}\mathrm{r} _{2}$

  4. $I _{2}$


Correct Option: A
Explanation:

Fluorine $(F _2)$ is a halogen , which is a non-metal and has highest electronegativity, so it has maximum affinity for hydrogen. 

Which requires the highest energy for excitation?

  1. F

  2. Cl

  3. Br

  4. I


Correct Option: A
Explanation:

Fluorine has a small size thus it has a high nuclear charge and its electrons are strongly attracted towards the nucleus. Thus it requires high energy for excitation. Among halogen atoms, fluorine requires the highest energy for excitation.

Halogens means:

  1. ore forming elements

  2. sea salt products

  3. inert gases

  4. rare gases


Correct Option: B
Explanation:

Sea salt $\to$ like $Mgcl _{2},\ MgBr _{2}$ have halogens.  $\therefore$  Halogens are sea salt products

Which of the following has seven valence electrons?

  1. $Na^{+}$

  2. $Al$

  3. $F$

  4. $Ti$

  5. $B$


Correct Option: C
Explanation:

We know that halogens have 7 electrons in their valence shell.

$F, Cl, Br, I$ are halogens.
Hence, option $C$ is correct.

Which of the following statement is wrong? In the reaction $2KCl{ O } _{ 3 }+{ I } _{ 2 }\rightarrow 2KI{ O } _{ 3 }+{ Cl } _{ 2 }$?

  1. ${ Cl } _{ 2 }$ is more reactive than $I _{ 2 }$

  2. When $KCl{ O } _{ 3 }$ reacts with $I _{ 2 }$, ${ Cl } _{ 2 }$ is liberated

  3. $KCl{ O } _{ 3 }+{ I } _{ 2 }$ is a redox reaction and $I _{ 2 }$ is oxidized

  4. In the above reaction, $I _{ 2 }$ is reduced


Correct Option: D
Explanation:

the given reaction is

${ 2KClO } _{ 3 }+{ I } _{ 2 }\rightarrow { 2KIO } _{ 3 }+{ Cl } _{ 2 }$
in reactant,oxidation state of iodine in ${ I } _{ 2 }=0$
in product,oxidation state of iodine in${ IO } _{ 3 }^{ - }\quad $is 3
so,oxidation state of iodine change from 0 to5,so it is oxidlsed.

For electron affinity of halogens which of the following is correct?

  1. $Br>F$

  2. $F>Cl$

  3. $Br>Cl$

  4. $F>I$


Correct Option: D
Explanation:

  • Electron Gain Enthalpy is the energy released when one mole of an electron is added to gaseous atoms of an element. 
  • The correct order of Electron gain enthalpy of Fluorine family is,
$Cl>F>Br>I$
The reason for this is that the size of the fluorine atom is very small. So when an electron is added in the fluorine atom it will suffer more electronegativity as all the electrons will be very close to each other and hence the electron gain enthalpy of chlorine is more negative than that of fluorine.

Chlorine has two naturally occuring isotopes $ _{ 17 }^{ 37 }{ Cl }$ and $ _{ 17 }^{ 35 }{ Cl }$ and average atomic mass of chlorine is $35.5$. The percentage of $ _{ 17 }^{ 37 }{ Cl }$ is:

  1. 25%

  2. 75%

  3. 40%

  4. 60%


Correct Option: A