Tag: chemistry

Questions Related to chemistry

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 ?

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

  1. MO

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

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

  4. $ MO _{2} $

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Correct Option: B

Which of the following is the most acidic?

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

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

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

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

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

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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:

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

  1. $Cl _2O _5$

  2. $Cl _2O$

  3. $Cl _2O _3$

  4. $Cl _2O _7$

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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 ?

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

  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

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Correct Option: C

The type of ions responsible for scum formation are:

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

  1. oxides

  2. hydroxides

  3. chlorides

  4. carbonates

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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?

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

  1. $CrO$

  2. $Cr _2O _3$

  3. $CrO _3$

  4. $Cr _2O _4$

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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 :

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

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

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

  3. $AO$

  4. $A _{2}O$

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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 $Ti=48$]:

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

  1. $TiO$

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

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

  4. $None\ of\ these$

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Correct Option: A

The pair of amphoteric oxides is: 

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

  1. $VO,\,C{r _2}{O _3}$

  2. ${V _2}{O _5},\,C{r _2}{O _3}$

  3. $V{O _2},\,C{r _2}{O _3}$

  4. ${V _2}{O _5},\,Cr{O _3}$

Show answer
Correct Option: B
Explanation:
An amphoteric compound is a molecule or ion that can react both as an acid and as a base. Many metals (such as copper, zinc, tin, lead, aluminium, and beryllium) form amphoteric oxides or hydroxides. 

Amphoterism depends on the oxidation states of the oxide. Al2O3 is an example of an amphoteric oxide.

 V2O5 and Cr2O3 are amphoteric oxides because both react with alkalies as well as acids.

So, option B is correct

Which of the following oxide is most acidic? 

chemistry chemistry of non-metals oxides of elements simple oxides oxygen

  1. $Na _2O$

  2. $MgO$

  3. $SiO _2$

  4. $Cl _2O _7$

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Correct Option: D
Explanation:

$Na _2O$ , MgO are basic oxides.

$Cl _2O _7$  has highest acidity because it is an oxide of non metal .
Non metallic oxides are acidic 
This oxide reacts with water to give $HClO _4$ i,e,. strong acid.
So,