Tag: simple oxides

Questions Related to simple oxides

$Pb{O} _{2}$ oxide is:

  1. basic

  2. acidic

  3. neutral

  4. amphoteric


Correct Option: D
Explanation:

The $Pb{ O } _{ 2 }$ behaves as acidic and basic property so it is called as amphoteric.

When $Pb{ O } _{ 2 }$ dissolved in a strong base $Pb{ O }{ H } _{ 6 }$ is obtained so it is an acidic property.
when $Pb{ O } _{ 2 }$ dissolved in HCl,$PbCl _{ 6 }$ is formed so it is a basic property.
Thus $PbO _{ 2 }$ behaves as amphoteric in nature.

Two oxides of a metal contain $50$% and $40$% metal (M) respectively. If the formula of first oxide is $MO _2$, the formula of second oxide will be:

  1. $MO _2$

  2. $MO _3$

  3. $M _2O$

  4. $M _2O _5$


Correct Option: B
Explanation:
$\text{Compound } 1\quad\quad\quad\quad 50\% M+50\% O$
$\text{formula}\quad\quad\quad\quad MO _2$
Let atomic weight of metal be $X,$
$\Longrightarrow MO _2:$    $\cfrac{16}{X}=\cfrac{1}{2}$
Hence atomic weight of metal $=32$
$\text{Compound }2:$ $40\% M=\cfrac{40}{32}=1.25=1\\60\%O=\cfrac{60}{16}=3.75=3$
$\therefore$ Formula is $MO _3$.

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