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Question
What is meant by rust?
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Solution
Iron reacts with moist air to acquire a coating of a brown flaky substance called rust.
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RELATED QUESTIONS
Define ‘redox reaction’. Give one example.
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MULTIPLE CHOICE QUESTIONS
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- reduction.
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TRUE \ FALSE
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\[\ce{NiO + H2 -> Ni + H2O}\]
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Give the general group study of hydrogen with reference to
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State whether the following conversion is oxidation or reduction:
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Divide the following reactions into oxidation and reduction half-reaction:
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Divide the following reactions into oxidation and reduction half-reaction:
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Divide the above equation into oxidation and reduction half-reactions.
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Name:
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Identify the reducing agent in the following reactions
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Identify the oxidising agent (oxidant) in the following reactions
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Identify the oxidising agent (oxidant) in the following reactions
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Which among the following are physical or chemical change?
Evaporation of petrol
Which among the following are physical or chemical change?
Curding of milk
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?
A silver article generally turns black when kept in the open for a few days. The article when rubbed with toothpaste again starts shining.
- Why do silver articles turn black when kept in the open for a few days? Name the phenomenon involved.
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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.
On adding a drop of barium chloride solution to an aqueous solution of sodium sulphite, white precipitate is obtained :
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You are provided with two containers made up of copper and aluminium. You are also provided with solutions of dilute HCl, dilute HNO3, ZnCl2 and water. In which of the above containers, can these solutions be kept?
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______ is a metal that has a high resistance to corrosion.
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Zn in ZnSO4
Identify the type of chemical reaction given below:
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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:
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