# Redox Reaction Test 3

Total Questions:50 Total Time: 75 Min

Remaining:

## Questions 1 of 50

Question:Max. number of moles of electrons taken up by one mole of $$NO_3^ -$$ when it is reduced to

$$N{H_3}$$

$$N{H_2}OH$$

$$NO$$

$$N{O_2}$$

## Questions 2 of 50

Question:In the reaction $$3Mg + {N_2} \to M{g_3}{N_2}$$

Magnesium is reduced

Magnesium is oxidized

Nitrogen is oxidized

None of these

## Questions 3 of 50

Question:When sodium metal is dissolved in liquid ammonia, blue colour solution is formed. The blue colour is due to

Solvated $$N{a^ + }$$ions

Solvated electrons

Solvated $$NH_2^ -$$ ions

Solvated protons

## Questions 4 of 50

Question:Following reaction describes the rusting of iron $$4Fe + 3{O_2}\, \to \,4F{e^{3 + }} + 6{O^{2 - }}$$. Which one of the following statement is incorrect

This is an example of a redox reaction

Metallic iron is reduced to $$F{e^{3 + }}$$

$$F{e^{3 + }}$$ is an oxidising agent

Metallic iron is a reducing agent

## Questions 5 of 50

Question:In the following reaction, $$3B{r_2} + 6CO_3^{2 - } + 3{H_2}O = 5B{r^ - } + BrO_3^ - + 6HC{O_3}$$

Bromine is oxidised and carbonate is reduced

Bromine is reduced and water is oxidized

Bromine is neither reduced nor oxidized

Bromine is both reduced and oxidized

## Questions 6 of 50

Question:In the following reaction, $$4P + 3KOH + 3{H_2}O \to 3K{H_2}P{O_2} + P{H_3}$$

P is oxidized as well as reduced

P is reduced only

P is oxidised only

None of these

## Questions 7 of 50

Question:In the following reaction $$C{r_2}O_7^ - + 14{H^ + } + 6{I^ - } \to \,$$ $$2C{r^{3 + }} + 3{H_2}O + 3{I_2}$$ Which element is reduced

$$Cr$$

$$H$$

$$O$$

$$I$$

## Questions 8 of 50

Question:The conversion of sugar $${C_{12}}{H_{22}}{O_{11}}\, \to \,\,C{O_2}$$ is

Oxidation

Reduction

Neither oxidation nor reduction

Both oxidation and reduction

## Questions 9 of 50

Question:Several blocks of magnesium are fixed to the bottom of a ship to

Keep away the sharks

Make the ship lighter

Prevent action of water and salt

Prevent puncturing by under-sea rocks

## Questions 10 of 50

Question:Which of the following behaves as both oxidising and reducing agents

$${H_2}S{O_4}$$

$$S{O_2}$$

$${H_2}S$$

$$HN{O_3}$$

## Questions 11 of 50

Question:The reaction $${H_2}S + {H_2}{O_2} \to 2{H_2}O + S$$ shows

Oxidizing action of $${H_2}{O_2}$$

Reducing action of $${H_2}{O_2}$$

Alkaline nature of $${H_2}{O_2}$$

Acidic nature of $${H_2}{O_2}$$

## Questions 12 of 50

Question:Which of the following is not a reducing agent

$$NaN{O_2}$$

$$NaN{O_3}$$

$$HI$$

$$SnC{l_2}$$

## Questions 13 of 50

Question:Which of the following acid possesses oxidising, reducing and complex forming properties

$$HN{O_3}$$

$${H_2}S{O_4}$$

$$HCl$$

$$HN{O_2}$$

## Questions 14 of 50

Question:Which one is oxidising substance

$${C_2}{H_2}{O_2}$$

$$CO$$

$${H_2}S$$

$$C{O_2}$$

## Questions 15 of 50

Question:The compound that can work both as oxidising and reducing agent is

$$KMn{O_4}$$

$${H_2}{O_2}$$

$$Ba{O_2}$$

$${K_2}C{r_2}{O_7}$$

## Questions 16 of 50

Question:Which one is oxidising agent in the reaction below $$2CrO_4^{2 - } + 2{H^ + } \to C{r_2}O_7^{2 - } + {H_2}O$$

$${H^ + }$$

$$C{r_2}O_4^ -$$

$$C{r^{ + + }}$$

None of these

## Questions 17 of 50

Question:In the conversion $$B{r_2}\, \to \,BrO_3^ - ,$$ the oxidation state of bromine changes from

1 to – 1

0 to – 1

0 to + 5

0 to – 5

## Questions 18 of 50

Question:In the chemical reaction $$C{l_2} + {H_2}S \to 2HCl + S$$ , the oxidation number of sulphur changes from

0 to 2

2 to 0

2 to 0

2 to – 1

## Questions 19 of 50

Question:Oxidation number of cobalt in $$K[Co{(CO)_4}]$$ is

1

3

1

3

## Questions 20 of 50

Question:When $${K_2}C{r_2}{O_7}$$ is converted to $${K_2}Cr{O_4},$$ the change in the oxidation state of chromium is

0

6

4

3

## Questions 21 of 50

Question:Maximum oxidation state of Cr is

3

4

6

7

## Questions 22 of 50

Question:In which of the following compound transition metal has zero oxidation state

$$Cr{O_5}$$

$$N{H_2}.N{H_2}$$

$$NOCl{O_4}$$

$$[Fe{(CO)_5}]$$

## Questions 23 of 50

Question:Carbon is in the lowest oxidation state in

$$C{H_4}$$

$$CC{l_4}$$

$$C{F_4}$$

$$C{O_2}$$

## Questions 24 of 50

Question:Oxidation number of carbon in $${H_2}{C_2}{O_4}$$ is

4

3

2

2

## Questions 25 of 50

Question:The sum of the oxidation numbers of all the carbons in $${C_6}{H_5}CHO$$ is

2

0

4

4

## Questions 26 of 50

Question:Which one of the following has the highest oxidation number of iodine

$$K{I_3}$$

$$KI$$

$$I{F_5}$$

$$KI{O_4}$$

## Questions 27 of 50

Question:The oxidation number of N in $${N_2}H_5^ +$$

3

(– 2)

1

2

## Questions 28 of 50

Question:In which of the following compounds the oxidation number of carbon is maximum

$$HCHO$$

$$CHC{l_3}$$

$$C{H_3}OH$$

$${C_{12}}{H_{22}}{O_{11}}$$

## Questions 29 of 50

Question:The oxidation states of the most electronegative element in the products of the reaction of $$Ba{O_2}$$with dilute $${H_2}S{O_4}$$ are

0 and – 1

1 and – 2

2 and 0

2 and + 1

## Questions 30 of 50

Question:The highest oxidation state of $$Mn$$ is shown by

$${K_2}Mn{O_4}$$

$$KMn{O_4}$$

$$Mn{O_2}$$

$$M{n_2}{O_2}$$

$$MnO$$

## Questions 31 of 50

Question:The oxidation number of carbon in $$C{H_2}O$$ is

2

2

0

4

## Questions 32 of 50

Question:Sulphur has lowest oxidation number in

$${H_2}S{O_3}$$

$$S{O_2}$$

$${H_2}S{O_4}$$

$$Ca,\,\,K,\,\,Li$$

## Questions 33 of 50

Question:The oxidation number and covalency of sulphur in the sulphur molecule $$({S_8})$$ are respectively

0 and 2

6 and 8

0 and 8

6 and 2

## Questions 34 of 50

Question:In ferrous ammonium sulphate oxidation number of $$Fe$$ is

3

2

1

2

## Questions 35 of 50

Question:When $$KMn{O_4}$$ is reduced with oxalic acid in acidic solution, the oxidation number of $$Mn$$ changes from

7 to 4

6 to 4

7 to 2

4 to 2

## Questions 36 of 50

Question:Oxygen has oxidation states of +2 in the

$${H_2}{O_2}$$

$$C{O_2}$$

$${H_2}O$$

$$O{F_2}$$

## Questions 37 of 50

Question:The element exhibiting most stable $$+ \,2$$ oxidation state among the following is

$$Ag$$

$$Fe$$

$$Sn$$

$$Pb$$

## Questions 38 of 50

Question:Oxidation number of sulphur in $${S_2}O_3^{2 - }$$is

2

2

6

0

## Questions 39 of 50

Question:The oxidation number of nickel in $${K_4}[Ni{(CN)_4}]$$ is

2

1

2

0

## Questions 40 of 50

Question:The oxidation number of fluorine in $${F_2}O$$ is

1

1

2

2

## Questions 41 of 50

Question:Oxidation number of $$Fe$$ in $${K_3}[Fe{(CN)_6}]$$ is

2

3

1

4

## Questions 42 of 50

Question:Oxidation number of $$N$$ in $$N{H_3}$$ is

3

3

0

5

## Questions 43 of 50

Question:Starch paper is used to test for the presence of

Iodine

Oxidising agent

Iodide ion

Reducing agent

## Questions 44 of 50

Question:How many moles of $${K_2}C{r_2}{O_7}$$ can be reduced by 1 mole of $$S{n^{2 + }}$$

1/3

1/6

2/3

1

## Questions 45 of 50

Question:$$2MnO_4^ - + 5{H_2}{O_2} + 6{H^ + } \to 2\,\,Z + 5{O_2} + 8{H_2}O$$. In this reaction Z is

$$M{n^{ + 2}}$$

$$M{n^{ + 4}}$$

$$Mn{O_2}^{}$$

$$Mn$$

## Questions 46 of 50

Question:What is 'A' in the following reaction $$2F{e^{3 + }}_{(aq)} + S{n^{2 + }}_{(aq)} \to 2F{e^{2 + }}_{(aq)} + A$$

$$S{n^{3 + }}_{(aq)}$$

$$S{n^{4 + }}_{(aq)}$$

$$S{n^{2 + }}_{(aq)}$$

Sn

## Questions 47 of 50

Question:In which of the following reactions there is no change in valency

$$4KCl{O_3}\, \to \,3KCl{O_4} + KCl$$

$$C{l_2}$$

$$Ba{O_2} + {H_2}S{O_4}\, \to \,\,BaS{O_4} + {H_2}{O_2}$$

$$2BaO + {O_2}\, \to \,2Ba{O_2}$$

## Questions 48 of 50

Question:The equivalent weight of phosphoric acid $$({H_3}P{O_4})$$ in the reaction $$NaOH + {H_3}P{O_4} \to Na{H_2}P{O_4} + {H_2}O$$ is

25

49

59

98

## Questions 49 of 50

Question:What is the equivalent mass of $$IO_4^ -$$ when it is converted into $${I_2}$$ in acid medium

M/6

M/7

M/5

M/4

None of these

## Questions 50 of 50

Question:For decolourization of 1 mole of $$KMn{O_4}$$ , the moles of $${H_2}{O_2}$$ required is