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

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

  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
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

ZnO reacts with HCl to form ZnCl2 and water, and with NaOH to form Na2ZnO2 (sodium zincate) and water. This dual behavior confirms that ZnO is amphoteric.

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

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

  1. acidic oxide

  2. basic oxide

  3. amphoteric oxide

  4. none of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

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

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

Non-metals combine with oxygen to form usually:

  1. basic oxides

  2. neutral oxides

  3. acidic oxides

  4. amphoteric oxides
Reveal answer Fill a bubble to check yourself
C Correct answer
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 

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

Which one of the following is an amphoteric
oxide?

  1. $Na _{2}O$
  2. $SO _{2}$
  3. $B _{2}O _{3}$
  4. $\mathrm{Z}\mathrm{n}\mathrm{O}$
Reveal answer Fill a bubble to check yourself
D Correct answer
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 $\mathrm H _{2}O$.

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

Which of the following is not a normal oxide?

  1. $\mathrm{N}\mathrm{a} _{2}\mathrm{O}$
  2. $\mathrm{Al} _{2}\mathrm{O} _{3}$
  3. $\mathrm{K}\mathrm{O} _{2}$
  4. $\ \mathrm{M}\mathrm{g}\mathrm{O}$
Reveal answer Fill a bubble to check yourself
C Correct answer
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.

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

Which of the following elements forms amphoteric oxides?

  1. Beryllium

  2. Aluminium

  3. Zinc

  4. All
Reveal answer Fill a bubble to check yourself
D Correct answer
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.