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प्रश्न
Give scientific reason.
It is reccommended to use air tight container for storing oil for long time.
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उत्तर
- When edible oil is left aside for long time, it undergoes air oxidation.
- Due to this, the taste and smell of oil changes and it becomes rancid. If food is cooked in this oil, its taste also changes.
- Thus, the oil will become unfit for consumption.
- The process of oxidation reaction of oil can be slowed down by storing it in air tight container.
Hence, it is recommended to use air tight container for storing oil for long time.
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संबंधित प्रश्न
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\[\ce{PbS_{(s)} + 4H2O2_{(aq)} -> PbSO4_{(s)} + 4H2O_{(l)}}\]
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- Which substance is oxidised?
Identify the component oxidised in the following reaction:
\[\ce{H2S + Cl2 -> S + 2HCl}\]
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The addition of hydrogen to a substance is called ______ whereas removal of hydrogen is called ______.
Give an example of an oxidation reaction.
Is oxidation an exothermic or an endothermic 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.
In the reaction represented by the following equation:
\[\ce{CuO_{(s)} + H2_{(g)} -> Cu_{(s)} + H2O_{(l)}}\]
- name the substance oxidised
- name the substance reduced
- name the oxidising agent
- name the reducing agent
In the context of redox reactions, the removal of hydrogen from a substance is known as ______.
Indicate which of the following statement is true and which is false:
The removal of hydrogen from a substance is called reduction.
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Define reduction.
Define redox reaction.
Identify from the following reaction the reactants that undergo oxidation and reduction.
\[\ce{2Ag2O → 4 Ag + O2 \uparrow}\]
Identify from the reaction the reactants that undergo oxidation and reduction.
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burning
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reaction with oxygen
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Divide the above equation into oxidation and reduction half-reactions.
Reacting with water, an active metal produces
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Choose terms from the options given in brackets to complete this sentence.
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(CuO, H2, Cu, H2O)
Name:
a gas that is oxidizing as well as a reducing agent.
Explain the term oxidation in term of addition and removal of oxygen/hydrogen with a suitable example.
Explain the term redox reaction with an example involving the reaction of hydrogen sulphide with chlorine.
Identify the following reactions as oxidation or reduction
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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 oxidising agent (oxidant) in the following reactions
`"V"_2"O"_5 + 5"Ca" -> 2"V" + 5"CaO"`
Which among the following are physical or chemical change?
Burning of Liquefied Petroleum Gas (LPG)
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Curding of milk
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Explain this observation giving suitable reason.
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Identify the following reactions as oxidation/reduction/redox reaction
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Identify the following reactions as oxidation/reduction/redox reaction
2Mg +O2 → 2MgO
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Define oxidation number.
Find the oxidation number of the element in the following compound.
Zn in ZnSO4
State the change in colour observed in following case mentioning the reason:
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