Chemistry

Oxidation States and Oxides

334 Questions

Oxidation states represent the degree of oxidation of an atom in a chemical compound. This topic covers calculating valency, classifying oxides as acidic or basic, and understanding thermal decomposition. These concepts are frequently tested in chemistry sections across multiple competitive examination platforms.

calculating oxidation statesclassification of oxidesvalency determinationthermal decompositionstability of metal oxides

Oxidation States and Oxides Questions

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

Pick the group which does not contain a neutral oxide.

  1. $NO _2, P _4O _{10}, Al _2O _3, NO$
  2. $MgO, N _2O _5, SO _3, N _2O$
  3. $CO _2, SO _3, CaO, XeO _3$
  4. $CO, SiO _2, SnO _2, Na _2O _3$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Neutral oxide are those which do not react with acids as well as bases such as $NO,{ N } _{ 2 }O,CO,{ O } _{ 2 }{ F } _{ 2 }$.

So only option $C$ does not contain neutral oxide.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Which of the following is not correct observation based on Ellingham diagram?

  1. A metal can reduce the oxide of other metal which lies above it in Ellingham diagram
  2. $CO$ is more effective than $C$ as reducing agent below $170^{o}C$
  3. $\Delta G^{o}$ metal oxide is higher than of $CO _{2}$ hence oxidation of metal sulphides to oxides is not favourable

  4. Need for conversion of metal sulphide to metal oxide before reduction can be explained thermodynamically
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

As moving down of bottom of diagram metals becomes more reactive oxides will be hard to reduce.A given metal can reduce the oxides of other metal which lies above it in Ellingham diagram.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

The oxidation state of nitrogen in ammonia molecule is -3.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The oxidation state of nitrogen in ammonia ($NH _3$) molecule is -3.
Let x be the oxidation state of nitrogen in ammonia. The oxidation state of hydrogen is $ \displaystyle +1$ .
$ \displaystyle x + 3 (+1)=0$
$ \displaystyle x+3=0$
$ \displaystyle x=-3$
Multiple choice

O

  1. osmium

  2. oxygen

  3. nobelium

  4. molybdenium
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The chemical symbol O stands for oxygen, which is essential for respiration in most living organisms. Osmium is represented by Os, and nobelium is represented by No.

Multiple choice

Magnesium nitrite

  1. MgNO3

  2. Mg2NO3

  3. Mg2NO2

  4. Mg(NO2)2
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Magnesium (Mg) has a 2+ charge, and the nitrite ion (NO2) has a 1- charge. To balance the charges, you need two nitrite ions for every one magnesium ion, resulting in Mg(NO2)2.

Multiple choice

Tetranitrogen heptoxide

  1. NO

  2. N4O7

  3. N3O6

  4. N4O9
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The prefix 'tetra-' means four and 'hepta-' means seven. Therefore, tetranitrogen heptoxide corresponds to N4O7.

Multiple choice

Magnesium nitrite

  1. MgNO3

  2. Mg2NO3

  3. Mg2NO2

  4. Mg(NO2)2
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Magnesium (Mg) has a 2+ charge, and the nitrite ion (NO2) has a 1- charge. To balance the charges, you need two nitrite ions for every one magnesium ion, resulting in Mg(NO2)2.

Multiple choice

Sr(OH)2

  1. Strontium oxygen hydride

  2. strontium (II) hydroxide

  3. strontium (II) oxygen hydride

  4. strontium hydroxide
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Sr is strontium and OH is the hydroxide polyatomic ion. Since strontium is in group 2, it forms a 2+ ion, and the formula is Sr(OH)2.