Advertisements
Advertisements
प्रश्न
Identify from the reaction the reactants that undergo oxidation and reduction.
\[\ce{NiO + H2 -> Ni + H2O}\]
Advertisements
उत्तर
In a reaction, nickel oxide is changing to nickel. That is, oxygen is being removed from nickel oxide. Removal of oxygen from a substance is called reduction, so nickel oxide undergoes reduction.
In a reaction, hydrogen is changing to H2O. That is, oxygen is being added to hydrogen. Addition of oxygen to a substance is called oxidation, so hydrogen undergoes oxidation.
The reactions in which oxidation and reduction take place simultaneously are called Redox reactions.
संबंधित प्रश्न
Corrosion can be prevented by using ……………. solution.
The chemical formula for rust is.............. .
Why does the colour of copper sulphate solution change when an iron nail is dipped in it?
A shiny brown-coloured element ‘X’ on heating in air becomes black in colour. Name the element ‘X’ and the black-colored compound formed.
What is meant by rust?
In the following reaction between lead sulphide and hydrogen peroxide:
\[\ce{PbS_{(s)} + 4H2O2_{(aq)} -> PbSO4_{(s)} + 4H2O_{(l)}}\]
- Which substance is reduced?
- Which substance is oxidised?
When SO2 gas is passed through saturated solution of H2S, the following reaction occurs:
\[\ce{SO2 + 2H2S -> 2H2O + 3S}\]
In this reaction, which substance is oxidised and which one is reduced?
Give an example of an oxidation reaction.
Give one example of an oxidation-reduction reaction which is also a combination reaction.
Give one example of an oxidation-reduction reaction which is also a displacement reaction.
Explain the following in terms of gain or loss of oxygen with one example:
Oxidation
When copper powder is heated strongly in air, it forms copper oxide. Write a balanced chemical equation for this reaction. Name
- substance oxidised, and
- substance reduced.
Define the following in terms of gain or loss of hydrogen with one example:
Reduction
When a magnesium ribbon is heated, it burns in air to form magnesium oxide. Write a balanced chemical equation for this reaction. Name
- substance oxidised, and
- substance reduced.
In the context of redox reactions, the removal of hydrogen from a substance is known as ______.
In order to prevent the spoilage of potato chips, they are packed in plastic bags in an atmosphere of ______.
The process of respiration is ______.
You are given the following chemical equation:
\[\ce{Mg_{(s)} + CuO_{(s)} -> MgO_{(s)} + Cu_{(s)}}\]
This equation represents:
Fill in the blank
In redox reaction oxidation and reduction occur ............................
Define an oxidation reaction.
Give scientific reason.
It is reccommended to use air tight container for storing oil for long time.
Explain the following in term of gain or loss of oxygen with two examples.
Oxidation
In what respect does hydrogen differ from:
alkali metals
Describe briefly the ionic concept of oxidation and reduction. Give an equation to illustrate.
State, giving reason, whether the substances printed in bold letters have been oxidized or reduced.
Mg + 2HCl → MgCl2 + H2
State whether the following conversion is oxidation or reduction:
Cu2+ + 2 e-→ Cu
In the following reaction: A+ + B → A + B+. Write half-reactions for this reaction and name:
- oxidizing agent
- substance oxidized
- reducing agent
Divide the following reactions into oxidation and reduction half-reaction:
Zn + Pb2+→ Pb + Zn 2+
Divide the following reactions into oxidation and reduction half-reaction:
Cl2 + 2Br- → Br2 + 2Cl-
A metal oxide that is reduced by hydrogen is
Complete and balance the following equation:
H2 + S → ___________
Complete and balance the following equation:
Zn +_________________→ZnCl2 + H2
Complete and balance the following equation:
CuO +__________→ Cu +___________
State the condition and give balanced equation for the conversion of coke to water gas.
Explain the term oxidation in term of addition and removal of oxygen/hydrogen with a suitable example.
State what is oxidising agent. Give an example of oxidising agent in the gaseous, liquid, and solid form.
Oxidation is a process which involves ____________.
The process of reduction involves ____________.
Select the oxidising agent for the following reaction:
\[\ce{H2S + I2 -> 2HI + S}\]
In the reaction of iron with copper sulphate solution:
CuSO4 + Fe → Cu + FeSO4
Which option in the given table correctly represents the substance oxidized and the reducing agent?
| OPTION | Substance Oxidized | Reducing Agent |
| A | Fe | Fe |
| B | Fe | FeSO4 |
| C | Cu | Fe |
| D | CuSO4 | Fe |
Identify the reducing agent in the following reactions -
`"H"_2"O" + "F"_2 -> "HF" + "HOF"`
Identify the oxidising agent (oxidant) in the following reactions
`2"Mg" + "O"_2 -> 2"MgO"`
Identify the oxidising agent (oxidant) in the following reactions
`"V"_2"O"_5 + 5"Ca" -> 2"V" + 5"CaO"`
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
Some bubbles of a gas are seen when lead (Pb) is reacted with the acid.
Explain this observation giving suitable reason.
Why do we store silver chloride in a dark coloured bottle?
What happens when zinc granules are treated with dilute solution of H2SO4, HCl, HNO3, NaCl and NaOH Also write the chemical equations if reaction oçcurs.
What is a redox reaction?
Oxidizing agents are otherwise called ______.
Choose the odd one out and write the reason:
Identify the following reactions as oxidation/reduction/redox reaction
CuO+H2 → Cu+H2O
Identify the following reactions as oxidation/reduction/redox reaction
2Mg +O2 → 2MgO
Find the oxidation number of the element in the following compound.
N in NH3
In the redox reaction:
MnO2 + 4HCl → MnCl2 + 2H2O + Cl2
Metals are good ______.
