# Redox Reaction Test 2

Total Questions:50 Total Time: 75 Min

Remaining:

## Questions 1 of 50

Question:In the course of a chemical reaction an oxidant

Loses electrons

Gains electrons

Both loses and gains electron

Electron change takes place

## Questions 2 of 50

Question:$$2CuI\, \to Cu + Cu{I_2}$$, the reaction is

Redox

Neutralisation

Oxidation

Reduction

## Questions 3 of 50

Question:$${H_2}S$$ reacts with halogens, the halogens

Form sulphur halides

Are oxidized

Are reduced

None of these

## Questions 4 of 50

Question:$${H_2}{O_2}$$reduces $${K_4}Fe{(CN)_6}$$

In neutral solution

In acidic solution

In non-polar solvent

In alkaline solution

## Questions 5 of 50

Question:One gas bleaches the colour of flowers by reduction while the other by oxidation

$$CO$$ and $$C{l_2}$$

$$S{O_2}$$ and $$C{l_2}$$

$${H_2}S$$ and $$B{r_2}$$

$$N{H_3}$$ and $$S{O_2}$$

## Questions 6 of 50

Question:Reduction involves

Loss of electrons

Gain of electrons

Increase in the valency of positive part

Decrease in the valency of negative part

## Questions 7 of 50

Question:In a reaction between zinc and iodine, in which zinc iodide is formed, what is being oxidized

Zinc ions

Iodide ions

Zinc atom

Iodine

## Questions 8 of 50

Question:Which one of the following reactions does not involve either oxidation or reduction

$$VO_2^ + \, \to \,{V_2}{O_3}$$

$$Na\, \to \,N{a^ + }$$

$$CrO_4^{2 - }\, \to \,C{r_2}O_7^{2 - }$$

$$Z{n^{2 + }}\, \to \,Zn$$

## Questions 9 of 50

Question:A reducing agent is a substance which can

Accept electron

Donate electrons

Accept protons

Donate protons

## Questions 10 of 50

Question:Which of the following is the most powerful oxidizing agent

$${F_2}$$

$$C{l_2}$$

$$B{r_2}$$

$${I_2}$$

## Questions 11 of 50

Question:Of the four oxyacids of chlorine the strongest oxidising agent in dilute aqueous solution is

$$HCl{O_4}$$

$$HCl{O_3}$$

$$HCl{O_2}$$

$$HOCl$$

## Questions 12 of 50

Question:Identify the correct statement about $${H_2}{O_2}$$

It acts as reducing agent only

It acts as both oxidising and reducing agent

It is neither an oxidiser nor reducer

It acts as oxidising agent only

## Questions 13 of 50

Question:In which of the following reactions $${H_2}{O_2}$$ is a reducing agent

$$2FeC{l_2} + 2HCl + {H_2}{O_2}\, \to \,2FeC{l_3} + 2{H_2}O$$

$$C{l_2} + {H_2}{O_2}\,\, \to \,\,2HCl + {O_2}$$

$$2HI + {H_2}{O_2}\, \to \,\,2{H_2}O + {I_2}$$

$${H_2}S{O_3} + {H_2}{O_2}\, \to \,\,{H_2}S{O_4} + {H_2}O$$

## Questions 14 of 50

Question:When $$NaCl$$ is dissolved in water the sodium ion becomes

Oxidised

Reduced

Hydrolysed

Hydrated

## Questions 15 of 50

Question:Strongest reducing agent is

$$K$$

$$Mg$$

$$Al$$

$$Br$$

$$Na$$

## Questions 16 of 50

Question:Which substance is serving as a reducing agent in the following reaction $$14{H^ + } + C{r_2}O_7^{2 - } + 3Ni \to 2C{r^{3 + }} + 7{H_2}O + 3N{i^{2 + }}$$

$${H_2}O$$

$$Ni$$

$${H^ + }$$

$$C{r_2}O_7^{2 - }$$

## Questions 17 of 50

Question:The oxidation number of Ba in barium peroxide is

6

2

1

4

## Questions 18 of 50

Question:$$HN{O_2}$$ acts both as reductant and oxidant, while $$HN{O_3}$$ acts only as oxidant. It is due to their

Solubility ability

Maximum oxidation number

Minimum oxidation number

Minimum number of valence electrons

## Questions 19 of 50

Question:Chlorine is in +1 oxidation state in

$$HCl$$

$$HCl{O_4}$$

$$ICl$$

$$C{l_2}O$$

## Questions 20 of 50

Question:The valency of Cr in the complex $${[Cr{({H_2}O)_4}C{l_2}]^ + }$$

1

3

5

6

## Questions 21 of 50

Question:The oxidation number of $$Mn$$ in $$MnO_4^{ - 1}$$ is

7

5

6

5

## Questions 22 of 50

Question:$$S{n^{ + + }}$$ loses two electrons in a reaction. What will be the oxidation number of tin after the reaction

2

Zero

4

2

## Questions 23 of 50

Question:The oxidation state of $$Mn$$ in $${K_2}Mn{O_4}$$

2

7

2

6

## Questions 24 of 50

Question:Oxidation number of oxygen in $${O_2}$$ molecule is

1

0

2

2

## Questions 25 of 50

Question:Sulphur has highest oxidation state in

$$S{O_2}$$

$${H_2}S{O_4}$$

$$N{a_2}{S_2}{O_3}$$

$$N{a_2}{S_4}{O_6}$$

## Questions 26 of 50

Question:The oxidation number of $$Fe$$ and $$S$$ in iron pyrites are

4, – 2

2, – 1

3, – 1.5

3, – 1

## Questions 27 of 50

Question:The oxidation number of nitrogen in $$NO_3^ -$$ is

1

2

3

5

## Questions 28 of 50

Question:Oxidation state of elemental carbon is

0

1

2

3

## Questions 29 of 50

Question:In which of the following compounds iron has lowest oxidation state

$$FeS{O_4}.{(N{H_4})_2}S{O_4}.6{H_2}O$$

$${K_4}Fe{(CN)_6}$$

$$Fe{(CO)_5}$$

$$F{e_2}O$$

$${K_2}Fe{O_4}$$

## Questions 30 of 50

Question:The oxidation number of hydrogen in $$M{H_2}$$ is

1

1

2

2

## Questions 31 of 50

Question:Oxidation number of iodine varies from

1 to +1

1 to +7

+3 to +5

1 to +5

## Questions 32 of 50

Question:When $$S{O_2}$$ is passed through acidic solution of potassium dichromate, then chromium sulphate is formed. Change in valency of chromium is

+4 to +2

+5 to +3

+6 to +3

+7 to +2

## Questions 33 of 50

Question:Oxidation number of $$P$$ in $$M{g_2}{P_2}{O_7}$$ is

3

2

5

3

## Questions 34 of 50

Question:The oxidation state of nitrogen is highest in

$${N_3}H$$

$$N{H_2}OH$$

$${N_2}{H_4}$$

$$N{H_3}$$

## Questions 35 of 50

Question:Oxidation number of $$P$$ in $$K{H_2}P{O_2}$$ is

1

3

5

4

## Questions 36 of 50

Question:The most common oxidation state of an element is -2. The number of electrons present in its outermost shell is

4

2

6

8

## Questions 37 of 50

Question:Oxidation state of 'S' in $${H_2}S{O_3}$$

3

6

4

2

## Questions 38 of 50

Question:Oxidation numbers of two $$Cl$$ atoms in bleaching powder, $$CaOC{l_2}$$ are

1, – 1

+ 1, – 1

+ 1, + 1

0, – 1

## Questions 39 of 50

Question:Select the compound in which chlorine is assigned the oxidation number +5

$$HCl{O_4}$$

$$HCl{O_2}$$

$$HCl{O_3}$$

$$HCl$$

## Questions 40 of 50

Question:Oxidation number of $$Mn$$ in $${K_2}Mn{O_4}$$ and $$MnS{O_4}$$ are respectively

+ 7, + 2

+ 6, + 2

+ 5, + 2

+ 2, + 6

## Questions 41 of 50

Question:Identify the element which can have highest oxidation numbers

$$N$$

$$O$$

$$Cl$$

$$C$$

## Questions 42 of 50

Question:What is the oxidation number of Co in $$[Co{(N{H_3})_4}ClN{O_2}]$$

2

3

4

5

## Questions 43 of 50

Question:The value of $$x$$ in the partial redox equation $$MnO_4^ - + 8{H^ + } + xe$$ $$\leftrightarrow$$ $$M{n^{2 + }} + 4{H_2}O$$ is

5

3

1

0

## Questions 44 of 50

Question:$${C_2}{H_6}(g) + n{O_2}\, \to \,C{O_2}\,(g) + {H_2}O\,(l)$$ In this equation, the ratio of the coefficients of $$C{O_2}$$ and $${H_2}O$$ is

1:01

2:03

3:02

1:03

## Questions 45 of 50

Question:The number of electrons involved in the reduction of $$C{r_2}O_7^{2 - }$$ in acidic solution to $$C{r^{3 + }}$$ is

0

2

3

5

## Questions 46 of 50

Question:When $$KMn{O_4}$$ acts as an oxidising agent and ultimately forms $${[\,Mn{O_4}]^{ - 2}},\,\,Mn{O_2},\,\,\,M{n_2}{O_3},\,\,M{n^{ + 2}}$$ then the number of electrons transferred in each case respectively is

4, 3, 1, 5

1, 5, 3, 7

1, 3, 4, 5

3, 5, 7, 1

## Questions 47 of 50

Question:Which one of the following nitrates will leave behind a metal on strong heating

Ferric nitrate

Copper nitrate

Manganese nitrate

Silver nitrate

## Questions 48 of 50

Question:To prevent rancidification of food material, which of the following is added

Reducing agent

Anti-oxidant

Oxidising agent

None of these

## Questions 49 of 50

Question:Prevention of corrosion of iron by zinc coating is called

Galvanization

Cathodic protection

Electrolysis

Photo–electrolysis

## Questions 50 of 50

Question:The metal used in galvanizing of iron is

$$Pb$$
$$Zn$$
$$Al$$
$$Sn$$