Common Oxidation States

Q. The number of d-electrons in $F{e}^{2+}$ (Atomic number of Fe =26) is not equal to that of the

1. p-electrons in Ne (At. no.=10)
2. s-electrons in Mg (At. no.=12)
3. d-electrons in Fe
4. p-electrons in $C{l}^{-}$ ( At. no. of Cl = 17)

Q. Assuming complete ionization, same moles of which of the following compounds will require the least amount of acidified $KMn{O}_4$ for complete oxidation?

1. $FeS{O}_3$
2. $Fe{C}_2{O}_4$
3. $Fe(N{O}_2{)}_2$
4. $FeS{O}_4$

Q.

Why are $M{n}^{2+}$ compounds more stable than $Fe2+$ towards oxidation to their +3 state?

Q.

What is the oxidation number of sodium in sodium amalgam?

Q. The oxidation state of chromium in the final product formed by the reaction between $KI$ and acidified potassium dichromate solution is:

1. $+2$
2. $+3$
3. $+4$
4. $+6$

Q.

How to balance this by oxidation number method $H_2{O}_2\left(aq\right)+F{e}^2\left(aq\right)+⟶F{e}^3\left(aq\right)+H_{2}O\left(l\right)$ [in acidic medium)

Q. A mixture of potassium chlorate, oxalic acid, and sulphuric acid is heated. During the reaction which element undergoes maximum change in oxidation number

1. S
2. Cl
3. H
4. C

Q.

Assign oxidation numbers to the underlined elements in each of the following species:

(a) NaH₂PO₄ (b) NaHSO₄ (c) H₄P₂O₇ (d) K₂MnO₄

(e) CaO₂ (f) NaBH₄ (g) H₂S₂O₇ (h) KAl(SO₄)₂.12 H₂O

Q.

What is the oxidation number of $\mathrm{Mn}$ in ${\mathrm{MnO}}_2$?

Q.

The oxidation number of arsenic trisulphide $\left({\text{As}}_{\text{2}}{\text{S}}_{\text{3}}\right)$ is ______.

1. $+1$

2. $+2$

3. $+3$

4. $-3$

Q.

Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?

Q.

Consider the elements:
Cs, Ne, I and F
Identify the element that exihibits only negative oxidation state.

Identidy the elements that exihibits only positive oxidation state.

Identify the element that exhibits both positive and negative oxidation states.

Identify the element which exihibits neither the negative nor does the positive oxidation state

Q.

What is the oxidation number of $\mathrm{Ca}$ in $\mathrm{CaO}$?

Q.

What may be the stable oxidation state of the transition element with the following d-electron configuration in the ground state of their atoms: $3d^3,3d^5,3d^8$ and $3d^4$ ?

Q. What is the oxidation no. Of B in NaBH4

Q.

To what extent do the electronic configurations decide the stability of oxidation states in the first series of the transition elements. Illustrate your answer with examples.

Q. The product of oxidation of $I^{-}$ with $Mn{O}_4^{-}$ in alkaline medium is:

1. $I_2$
2. $I{O}_3^{-}$
3. $I{O}^{-}$
4. $I{O}_4^{-}$

Q.

Which of the following oxide cannot be reduced with carbon to obtain the metal.

1. ${\mathrm{MnO}}_2$

2. ${\mathrm{Cr}}_2{\mathrm{O}}_3$

3. ${\mathrm{Al}}_2{\mathrm{O}}_3$

4. None of these

Q. Which of the following can act as oxidizing agent but not a reducing agent:

1. 
2. 
3. 
4. 

Q. 4. What is the oxidation no of Fe in the compound Ca2(Fe(CN)6).and also give its iupac name

Q. $Cl{O}_2+Sb{O}_2^{-}\to Cl{O}_2^{-}+Sb(OH{)}_6^{-}$
The balanced form of the above reaction in basic medium using oxidation number method is:

1. $2Cl{O}_2+Sb{O}_2^{-}+2O{H}^{-}\to 2Cl{O}_2^{-}+Sb(OH{)}_6^{-}+2H_{2}O$
2. $Cl{O}_2+Sb{O}_2^{-}+2H_{2}O+O{H}^{-}\to Cl{O}_2^{-}+Sb(OH{)}_6^{-}$
3. $2Cl{O}_2+Sb{O}_2^{-}+2H_{2}O+2O{H}^{-}\to 2Cl{O}_2^{-}+Sb(OH{)}_6^{-}$
4. $2Cl{O}_2+4Sb{O}_2^{-}+2O{H}^{-}\to Cl{O}_2^{-}+4Sb(OH{)}_6^{-}+3H_{2}O$

Q. $HCl{O}_4$ can behave as:

1. Both (a) and (b)
2. Oxidizing agent
3. Reducing agent
4. None of the above

Q. The oxidation state shown by silicon when it combines with strongly electropositive metal is

1. –2
2. –4
3. 4
4. –2

Q.

Which of the following shows only negative oxidation states?

1. Iodine

2. Bromine

3. Fluorine

4. Chlorine

Q. Please explain the steps to balance a reaction using OXIDATION NUMBER METHOD

Q.

What types of oxides are formed by metals? Give one example of each.

Q.

The oxidation number of iodine in ${\mathrm{IO}}_4^{-}$ is .

1. $-1$

2. $+2$

3. $+7$

4. $+5$

Q. 48.What is the oxidation number of metal in TlI3

Q. How to find oxidation state for radical and ion? Explain separately.

Q.

The metal that reacts with cold water is

1. mercury

2. sodium

3. zinc

4. tungsten