Tag: chemistry

Questions Related to chemistry

Which is most basic oxide of chromium ?

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

  1. $ CrO $

  2. $ CrO _2 $

  3. $ CrO _3 $

  4. $ Cr _2O _3 $

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Correct Option: A

Which of the following oxide can be converted to metal easily ?

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

  1. ZnO

  2. HgO

  3. PbO

  4. $C{u _2}O$

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Correct Option: B

$ZnO+2HCl\longrightarrow  X+{H} _{2}O$
$ZnO+2NaOH\longrightarrow  Y+{H} _{2}O$
Identify $X,Y$ and the nature of $ZnO$ best described by the above reaction

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

  1. $X=Zn{Cl} _{2}$; $Y=NaZn{O} _{2}$; Nature of $ZnO$- Amphoteric

  2. $X=Zn{Cl} _{2}$; $Y={Na} _{2}Zn{O} _{2}$; Nature of $ZnO$- Amphoteric

  3. $X=Zn{Cl} _{2}$; $Y=NaZn{O} _{2}$; Nature of $ZnO$- Acidic

  4. $X=Zn{Cl} _{3}$; $Y=Zn{OH} _{2}$; Nature of $ZnO$- Basic

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Correct Option: B

Which IS BASIC OXIDE

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

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

  2. $B _{2}O _3$

  3. $Ga _{2}O$

  4. $InO$

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Correct Option: A
Explanation:

As metal oxides are basic and Tl2O3 makes salt and water after reacting with acid. 

An oxide which forms salts when it reacts with both acids and alkali is :

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

  1. acidic oxide

  2. basic oxide

  3. amphoteric oxide

  4. none of the above

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Correct Option: C
Explanation:

An oxide which forms salts when it reacts with both acids and alkali is knwn as amphoteric oxides. $e.g.$ $Al _2O _3$.

Which of the following is an amphoteric oxide?

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

  1. $ MgO $

  2. $ Al _2O _3 $

  3. $ SO _2 $

  4. $ P _2O _5 $

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Correct Option: B

Non-metals combine with oxygen to form usually:

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

  1. basic oxides

  2. neutral oxides

  3. acidic oxides

  4. amphoteric oxides

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Correct Option: C
Explanation:

non-metal oxides forms acid after diluting in water Eg. $\mathrm{H} _{2}C{O} _{3}, {H} _{2}S{O} _{4}$
$\therefore$   non metals combine with oxygen to from usually acidic oxcides because of its low electronegativity 

Which one of the following is an amphoteric
oxide?

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

  1. $Na _{2}O$

  2. $SO _{2}$

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

  4. $\mathrm{Z}\mathrm{n}\mathrm{O}$

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Correct Option: D
Explanation:


$\mathrm Na _{2}O $ and first group oxides are basic while non-metal oxides such as $\mathrm SO _{2}$ and $B _{2}O _{3} $ are acidic.
ZnO is amphoteric because it can reacts with acid as well as base to produce salt and $\mathrm H _{2}O$.

Which of the following is not a normal oxide?

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

  1. $\mathrm{N}\mathrm{a} _{2}\mathrm{O}$

  2. $\mathrm{Al} _{2}\mathrm{O} _{3}$

  3. $\mathrm{K}\mathrm{O} _{2}$

  4. $\ \mathrm{M}\mathrm{g}\mathrm{O}$

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Correct Option: C
Explanation:

$KO _2 \rightarrow K^+ O _2^-$
Hence, $KO _2$ is a super oxide with $O _2^-$ ion.
$Na _2O, Al _2O _3, M _gO$ are normal oxides with $O^{2-}$ ion.

Which of the following elements forms amphoteric oxides?

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

  1. Beryllium

  2. Aluminium

  3. Zinc

  4. All

Show answer
Correct Option: D
Explanation:

An amphoteric species is a molecule or ion that can react as an acid as well as base. The word amphoteric means both. Many metals such as copper, zinc, tin, lead, aluminium and beryllium form amphoteric oxides or hydroxides.