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प्रश्न
Identify from the reaction the reactants that undergo oxidation and reduction.
2Mg + O2 → 2MgO
\[\ce{2Mg + O2 ->[\Delta] 2MgO}\]
उत्तर १
In a reaction, magnesium is changing to magnesium oxide. That means, oxygen is being added to magnesium. Addition of oxygen to a substance is called oxidation, so magnesium undergoes oxidation.
उत्तर २
Mg undergoes oxidation and O2 undergoes reduction.
संबंधित प्रश्न
The chemical formula for rust is.............. .
Identify the substances that are oxidised and the substances that are reduced in the following reaction.
\[\ce{4Na(s) + O2(g) -> 2Na2O(s)}\]
When a magnesium ribbon is heated, it burns in air to form magnesium oxide. Write a balanced chemical equation for this reaction. Name (i) substance oxidised, and (ii) substance reduced.
The process of respiration is:
(a) an oxidation reaction which is endothermic
(b) a reduction reaction which is exothermic
(c) a combination reaction which is endothermic
(d) an oxidation reaction which is exothermic
Fill in the blank
In redox reaction oxidation and reduction occur ............................
Name the following:
The process in which oxygen is added or hydrogen is removed.
Define redox reaction.
TRUE \ FALSE
Hydrogen is a good oxidizing agent.
The colours of aqueous solutions of CuSO4 and FeSO4 as observed in the laboratory are:
(A) pale green and light blue respectively
(B) light blue and dark green respectively
(C) dark blue and dark green respectively
(D) dark blue and pale green respectively
Explain the following in term of gain or loss of oxygen with two examples.
Reduction
In what respect does hydrogen differ from:
alkali metals
Is it essential that oxidation and reduction must occur side by side in a chemical reaction? Explain
State, giving reason, whether the substances printed in bold letters have been oxidized or reduced.
Mg + 2HCl → MgCl2 + H2
Divide the following reactions into oxidation and reduction half-reaction:
Zn + Cu2+ → Cu + Zn 2+
Name:
an oxidizing agent that does not contain oxygen.
Name:
a substance that oxidizes concentrated HCl to chlorine.
Explain the term reduction in term of addition and removal of oxygen/hydrogen with a suitable example.
Oxidising agents are also called as ______ because they remove electrons form other substances.
Find the oxidation number of the elements in the following compounds.
- C in CO2
- Mn in MnSO4
- N in HNO3
Rusting of iron involves a chemical reaction which is a combination of:
The process of reduction involves ____________.
Select the oxidising agent for the following reaction:
\[\ce{H2S + I2 -> 2HI + S}\]
Identify the reducing agent in the following reactions
`2"H"_2 + "O"_2 -> 2"H"_2"O"`
Identify the oxidising agent (oxidant) in the following reactions
`"Pb"_3"O"_4 + 8"HCl" -> 3"PbCl"_2 + "Cl"_2 + 4"H"_2"O"`
Identify the oxidising agent (oxidant) in the following reactions
`2"Mg" + "O"_2 -> 2"MgO"`
Zinc liberates hydrogen gas when reacted with dilute hydrochloric acid whereas copper does not. Explain why?
The tendency of atoms to have eight electrons in the outer shell is known as ______.
The sum of the oxidation number of all atoms in a compound is ______.
Identify the following reactions as oxidation/reduction/redox reaction
Zn + CuSO4 → Cu + ZnSO4
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
What are reducing agents? Give examples.
Find the oxidation number of the element in the following compound.
Ca in CaH2
Identify the type of chemical reaction given below:
\[\ce{2Mg + O2 -> 2MgO}\]
It is recommended to use air tight containers for storing oil for a long time.
A reddish brown metal used in electrical wires when powdered and heated strongly turns black. When hydrogen gas is passed over this black substance, it regains its original colour. Based on this information answer the following questions:
- Name the metal and the black substance formed.
- Write balanced chemical equations for the two reactions involved in the above information
