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प्रश्न
Write the chemical formula of rust.
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उत्तर
Rust is hydrated iron (III) oxide (Fe2O3.xH2O).
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संबंधित प्रश्न
Corrosion can be prevented by using ……………. solution.
The chemical formula for rust is.............. .
What are anti-oxidants? Why are they added to fat and oil containing foods?
In the reaction represented by the equation:
MnO2 + 4HCl → MnCl2 + 2H2O + Cl2
(i) name the substance oxidised.
(ii) name the oxidising agent.
(iii) name the substance reduced.
(iv) name the reducing agent.
Give an example of an oxidation reaction.
Define oxidation in terms of gain or loss of hydrogen with one example.
In the context of redox reactions, the removal of hydrogen from a substance is known as:
(a) oxidation
(b) dehydration
(c) reduction
(d) dehydrogenation
Fill in the blank
Oxidation is the removal of ......................and addition of ....................
Name the following:
The process in which oxygen is added or hydrogen is removed.
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Identify from the following reaction the reactants that undergo oxidation and reduction.
\[\ce{2Ag2O → 4 Ag + O2 \uparrow}\]
Explain the following in term of gain or loss of oxygen with two examples.
Oxidation
Compare hydrogen with alkali metals on the basis of:
Oxide formation
Give the general group study of hydrogen with reference to
burning
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.
PbO + CO → Pb + CO2
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 + Pb2+→ Pb + Zn 2+
Divide the following reactions into oxidation and reduction half-reaction:
Zn + Cu2+ → Cu + Zn 2+
Reacting with water, an active metal produces
Which of the following statements about hydrogen is incorrect?
For the reaction PbO + H2→ Pb + H2O, which of the following statements is wrong?
Name:
a gas that is oxidizing as well as a reducing agent.
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State what is oxidising agent. Give an example of oxidising agent in the gaseous, liquid, and solid form.
Select the correct answer from the symbol in the bracket.
The element, which like hydrogen is a strong reducing agent.
Balance the given chemical reaction as per the instructions below.
\[\ce{NaOH + H2SO4 -> Na2SO4 + H2O}\]
Oxidation means losing electrons then what is reduction?
Identify the following reactions as oxidation or reduction
- Na → Na+ + e
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\[\ce{H2S + I2 -> 2HI + S}\]
Identify the reducing agent in the following reactions
`"Fe"_2"O"_3 + 3"CO" -> 2"Fe" + 3"CO"_2`
Identify the oxidising agent (oxidant) in the following reactions
`"V"_2"O"_5 + 5"Ca" -> 2"V" + 5"CaO"`
Identify the oxidising agent (oxidant) in the following reactions.
`"CuO" + "H"_2 -> "Cu" + "H"_2"O"`
Which among the following are physical or chemical change?
Burning of Liquefied Petroleum Gas (LPG)
Which among the following are physical or chemical change?
Curding of milk
Which among the following are physical or chemical change?
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Explain this observation giving suitable reason.
Why do we store silver chloride in a dark coloured bottle?
Zinc liberates hydrogen gas when reacted with dilute hydrochloric acid whereas copper does not. Explain why?
Mention some oxidation reactions that occur in daily life.
The formation of brown colour on the freshly unit surface of vegetables and fruits is because ______ of organic compounds present in them.
The sum of the oxidation number of all atoms in a compound is ______.
______ is a metal that has a high resistance to corrosion.
Choose the odd one out and write the reason:
Identify the following reactions as oxidation/reduction/redox reaction
2Mg +O2 → 2MgO
Find the oxidation number of the element in the following compound.
Ca in CaH2
Find the oxidation number of the element in the following compound.
Mg in MgO
Find the oxidation number of the element in the following compound.
N in NH3
State the change in colour observed in following case mentioning the reason:
Copper powder is strongly heated in air.
