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प्रश्न
When a magnesium ribbon burns in air with a dazzling flame and forms a white ash, is magnesium oxidised or reduced? Why?
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उत्तर
Magnesium gets oxidised because oxygen is added to the substance (Mg). The chemical reaction is given as follows:
2Mg + O2 → 2MgO
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संबंधित प्रश्न
Explain the following in term Oxidation of gain or loss of oxygen with two example.
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What is an oxidation reaction? Identify in the following reaction (i) the substance oxidised, and (ii) the substance reduced:
ZnO + C → Zn + CO
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SO2 + 2H2S → 2H2O + 3S
In this reaction, which substance is oxidised and which one is reduced?
You are given the following chemical equation:
Mg (s) + CuO (s) → MgO (s) + Cu (s)
This equation represents:
(a) decomposition reaction as well as displacement reaction
(b) combination reaction as well as double displacement reaction
(c) redox reaction as well as displacement reaction
(d) double displacement reaction as well as redox reaction
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Define redox reaction.
MULTIPLE CHOICE QUESTIONS
The process of adding oxygen to a substance is called
- oxidation.
- reduction.
- displacement.
- hydrogenation.
In what respect does hydrogen differ from:
alkali metals
State whether the following conversion is oxidation or reduction:
PbO2 + SO2→ PbSO4
A metal oxide that is reduced by hydrogen is
Complete and balance the following equation:
Zn +_________________→ZnCl2 + H2
Explain the term redox reaction with an example involving the reaction of hydrogen sulphide with chlorine.
When the positive charge on an ion increases or the negative charge on them decreases it is called as _______.
Write chemical formula for rust.
Identify the oxidising agent (oxidant) in the following reactions
`3"Fe" + 4"H"_2"O" -> "Fe"_3"O"_4 + 4"H"_2`
Which among the following are physical or chemical change?
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Which among the following are physical or chemical change?
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- Write a balanced chemical equation for the reaction involved.
- What other name can be given to this precipitation reaction?
- On adding dilute hydrochloric acid to the reaction mixture, white precipitate disappears. Why?
