Tag: chemistry of non-metals

Questions Related to chemistry of non-metals

Which of the following oxide is an amphoteric oxide?

  1. $Bi _{2}O _{3}$

  2. $N _{2}O _{3}$

  3. $P _{4}O _{10}$

  4. $Sb _{2}O _{3}$


Correct Option: D
Explanation:
Those metal oxides which show basic as well as acidic behavior are known as amphoteric oxide
Here ${ Sb } _{ 2 }{ O } _{ 3 }$ oxide is an amphoteric oxide.

Two metallic oxides contain $27.6$% and $30$% oxygen respectively. If the formula of the first oxide is ${X} _{3}{O} _{4}$, that of the second will be ?

  1. $XO$

  2. $X{O} _{2}$

  3. ${X} _{2}{O} _{5}$

  4. ${X} _{2}{O} _{3}$


Correct Option: D
Explanation:

Solution:

Given that, formula of first oxide = $\\ { M } _{ 3 }{ O } _{ 4 }$

Let mass of the metal = x


% of metal in  $M _{ 3 }O _{ 4 }$ $=\dfrac { 3x }{ 3x+64 } \times 100$


but as given percentage$ =(100-27.6) = 72.4 %$ $\left( \dfrac { 3x }{ 3x+64 }  \right) \times 100=72.4$ or $x=56$


in 2nd oxide

$oxygen$ $=30%$

so for the metal $=70%$


so the ratio is,


$M:O=\dfrac { 70 }{ 56 } :\dfrac { 30 }{ 161.25 } :1.8752:3$ 


 so the second oxide is,


${ M } _{ 2 }{ O } _{ 3 }$


Hence the answer is

${ M } _{ 2 }{ O } _{ 3 }$.(${ X } _{ 2 }{ O } _{ 3 }$)

Two oxides of a metal contain 72.4% and 70% of metal respectively? If formula of 2nd oxide is $ M _{2}O _{3} $, find that of the first ?

  1. MO

  2. $ M _{3}O _{4} $

  3. $ M _{3}O _{2} $

  4. $ MO _{2} $


Correct Option: B

Which of the following is the most acidic?

  1. ${ P } _{ 2 }{ O } _{ 5}$

  2. ${ N } _{ 2 }{ O } _{ 5 }$

  3. ${ Sb } _{ 2 }{ O } _{ 5 }$

  4. ${ As } _{ 2 }{ O } _{ 5 }$


Correct Option: B
Explanation:

As the electronegativity value of the element increases. the acidic character of the oxide also increases.

Here among $N,P,SI$ and $As$ the most electronegative is $N$.

Thus the most acidic is $N _2O _5$.

The most acidic oxide among the following is:

  1. $Cl _2O _5$

  2. $Cl _2O$

  3. $Cl _2O _3$

  4. $Cl _2O _7$


Correct Option: D
Explanation:

$Cl _2O _7$ is most acidic because on reacting with water , it gives  most strongest acid than the other three i.e., $HClO _4$ .

So, $Cl _2O _4$ is most acidic 

Which of the following statements are not correct ?

  1. All C - O bonds in $CO _3^{2-}$ are equal but not in $H _2CO _3$

  2. All C - O bonds in $HCO _2^-$ are equal but not in $HCO _2H$.

  3. C - O bond length in $HCO _2^-$ is longer than C - O bond length in $CO _3^{2-}$

  4. C - O bond length in $HCO _2^-$ and C - O bond length in $CO _3^{2-}$ are equal


Correct Option: C

The type of ions responsible for scum formation are:

  1. oxides

  2. hydroxides

  3. chlorides

  4. carbonates


Correct Option: A
Explanation:

The scum is formed when soap is used in hard water and hard water consists of carbonate. For this process $Oxides$ ions responsible for scum formation.

Hence,
The option $(A)$ is correct.

Which of the following oxide is least basic?

  1. $CrO$

  2. $Cr _2O _3$

  3. $CrO _3$

  4. $Cr _2O _4$


Correct Option: A

An oxide of element $A$ was analysed and found to have mass ratio of $A$ to oxygen equal to $7:3$. Then formula of oxidation can be :

  1. $A _{3}O _{2}$

  2. $A _{2}O _{3}$

  3. $AO$

  4. $A _{2}O$


Correct Option: B

Titanium oxide $(TiO _{2})$ is heated in stream of hydrogen gas to give water and a new oxide $Ti _{x}O _{y}$. If $1.6\ gm$ of  $TiO _{2}$ produces $1.44\ gm$ of $Ti _{x}O _{y}$, the formula of new oxide is
[Atomic weight of $Ti=48$]:

  1. $TiO$

  2. $Ti _{2}O _{3}$

  3. $Ti _{2}O _{5}$

  4. $None\ of\ these$


Correct Option: A