Oxidation and Reduction Practice Questions:
The compound YBa2Cu3O7 which shows superconductivity has copper in the oxidation state …….. Assume that the rare earth element Yttrium is in its usual +3 oxidation state
(a) 3/7
(b) 7/3
(c) 3
(d) 7
Several blocks of magnesium are fixed to the bottom of a ship to
(a) Keep away the sharks
(b) Make the ship lighter
(c) Prevent action of water and salt
(d) Prevent puncturing by under-sea rocks
The oxidation state of I in H4IO–6 is
(a) + 7
(b) + 5
(c) + 1
(d) – 1
H2O2 is used as
(a) An oxidant only
(b) A reductant only
(c) An acid only
(d) An oxidant, a reductant and an acid
Which one of the following does not get oxidised by bromine water
(a) Fe+2 to Fe+3
(b) Cu+ to Cu+2
(c) Mn+2 to MnO4–
(d) Sn+2 to Sn+4
Related: questions about Mammals
A solution of sulphur dioxide in water reacts with H2S precipitating sulphur. Here sulphur dioxide acts as
(a) As oxidising agent
(b) A reducing agent
(c) An acid
(d) A catalyst
The oxidation number of hydrogen in LiH is
(a) + 1
(b) – 1
(c) 2
(d) 0
A reducing agent is a substance which can
(a) Accept electron
(b) Donate electrons
(c) Accept protons
(d) Donate protons
The conversion of PbO2 to Pb(NO3)2 is
(a) Oxidation
(b) Reduction
(c) Neither oxidation nor reduction
(d) Both oxidation and reduction
Oxidation number of carbon in H2C2O4 is
(a) + 3
(b) + 4
(c) + 2
(d) – 2
Related: Electrostatics multiple choice questions
The number of moles of KMnO4 reduced by one mole of KI in an alkaline medium is:
(a) One fifth
(b) five
(c) One
(d) Two
Which of the following statements is correct?
(a) Hydrogen has oxidation numbers –1 and +1
(b) Hydrogen has the same electronegativity as halogens
(c) Hydrogen will not be liberated at anode
(d) Hydrogen has the same ionization potential as alkali metals.
In the course of a chemical reaction, an oxidant
(a) Loses electrons
(b) Gains electrons
(c) Both loses and gain electron
(d) Electron change takes place
Oxidation state of elemental carbon is
(a) 0
(b) 1
(c) 2
(d) 3
Related: Amines online MCQ quiz
A metal ion M3+ after loss of three electrons in a reaction will have an oxidation number equal to
(a) Zero
(b) + 2
(c) + 3
(d) + 6
The maximum oxidation state of Cr is
(a) 3
(b) 4
(c) 6
(d) 7
Starch paper is used to test for the presence of
(a) Iodine
(b) Oxidizing agent
(c) Iodide ion
(d) Reducing agent
An element which never has a positive oxidation number in any of its compounds
(a) Boron
(b) Oxygen
(c) Chlorine
(d) Fluorine
Oxidation number of S in Na2SO4 is
(a) – 2
(b) + 2
(c) – 6
(d) + 6
Related: questions on Fluid Mechanics
The characteristic oxidation number of atoms in free metals is
(a) Minus one
(b) Any number
(c) One
(d) Zero
The oxidation state of I in IPO4 is
(a) +1
(b) +3
(c) +5
(d) +7
Phosphorus has the oxidation state of +3 in
(a) Orthophosphoric acid
(b) Phosphorus acid
(c) Metaphosphoric acid
(d) Pyrophosphoric acid
The oxidation state of sulphur in SO42– is
(a) 4
(b) 2
(c) 6
(d) – 6
The oxidation states of the most electronegative element in the products of the reaction of BaO2 with dilute H2SO4 are
(a) 0 and – 1
(b) – 1 and – 2
(c) – 2 and 0
(d) – 2 and + 1
Related: Protista Kingdom (Biology) Sample Paper
Oxidation state of ‘S’ in H2SO3
(a) + 3
(b) + 6
(c) + 4
(d) + 2
The oxidation number of carbon in CH2O is
(a) – 2
(b) + 2
(c) 0
(d) + 4
The oxidation state of each oxygen atom in Na2O2 is
(a) – 2 each
(b) – 2 and zero
(c) – 1 each
(d) None of these
A compound is in its low oxidation state. Then its will be
(a) Highly acidic
(b) Highly basic
(c) Highest oxidising property
(d) Half acidic, half basic
The most common oxidation state of an element is –2. The number of electrons present in its outermost shell is
(a) 4
(b) 2
(c) 6
(d) 8
Related: Gravitational force questions and answers
Oxidation numbers of two Cl atoms in bleaching powder, CaOCl2 are
(a) – 1, – 1
(b) + 1, – 1
(c) + 1, + 1
(d) 0, – 1
In the reaction between ozone and hydrogen peroxide, H2O2 acts as
(a) Oxidizing agent
(b) Reducing agent
(c) Bleaching agent
(d) Both oxidizing and bleaching agent
When KMnO4 is reduced with oxalic acid in acidic solution, the oxidation number of Mn changes from
(a) 7 to 4
(b) 6 to 4
(c) 7 to 2
(d) 4 to 2
When Fe2+ changes to Fe3+ in a reaction
(a) It loses an electron
(b) It gains an electron
(c) It loses a proton
(d) It gains a proton
Prevention of corrosion of iron by zinc coating is called
(a) Galvanization
(b) Cathodic protection
(c) Electrolysis
(d) Photo–electrolysis
Related: Chemical bonding questions
For the decolorization of 1 mole of KMnO4, the moles of H2O2 required is
(a) 1/2
(b) 3/2
(c) 5/2
(d) 7/2
The metal used in galvanizing of iron is
(a) Pb
(b) Zn
(c) Al
(d) Sn
When NaCl is dissolved in water, the sodium ion becomes?
(a) Oxidized
(b) Reduced
(c) Hydrolyzed
(d) Hydrated
Which one of the following nitrates will leave behind a metal on strong heating?
(a) Ferric nitrate
(b) Copper nitrate
(c) Manganese nitrate
(d) Silver nitrate
To prevent rancidification of food materials, which of the following is added?
(a) Reducing agent
(b) Anti-oxidant
(c) Oxidizing agent
(d) None of these
Related: Surface chemistry questions
HNO2 acts both as a reductant and an oxidant, while HNO3 acts only as an oxidant. It is due to their
(a) Solubility ability
(b) Maximum oxidation number
(c) Minimum oxidation number
(d) Minimum number of valence electrons
Of all the three common mineral acids, only sulphuric acid is found to be suitable for making the solution acidic because
(a) It does not react with KMnO4 or the reducing agent
(b) Hydrochloric acid reacts with KMnO4
(c) Nitric acid is an oxidizing agent which reacts with a reducing agent
(d) All of the above are correct
The oxidation number of As is
(a) + 2 and + 3
(b) + 3 and + 5
(c) + 3 and + 4
(d) None of these
The oxidation state of nitrogen in N3H is
(a) + 1/3
(b) + 3
(c) -1
(d) – 1/3
The oxidation number of C in CO2 is
(a) – 2
(b) + 2
(c) – 4
(d) + 4
my jee didn’t cleared this year, I will try next year
I have already practiced these questions now i need more questions for practice