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What is a common characteristic of all catalytic reactions?

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Important Questions on Changes Around Us

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

What is the primary purpose of using a catalyst in a reaction?

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Which of the following is a must condition for a chemical reaction to occur?

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Classify the following day to day activities based on chemical reactions by physical contact, solutions of reactants, heat, light, electricity and catalyst.

Burning of crackers during festivals.

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

How does the presence of a catalyst affect the energy required for a reaction?

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Which of the following best describes a chemical reaction based on physical contact?

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

When we put an iron nail in an open test tube containing water no reaction take place.

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Which of the following is true for most catalytic reactions?

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Mention the various conditions required for a chemical reaction to occur.

EASY

Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Give any two examples of chemical reactions on the basis of physical contact.

MEDIUM

Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Classify the following day to day activities based on chemical reactions by physical contact, solutions of reactants, heat, light, electricity and catalyst.

Copper vessel kept in open air for long time.

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

How can the rate of reaction be increased in a reaction without using a catalyst?

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

What role does a catalyst play in chemical reactions?

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

What happens when a matchstick is rubbed on the sides of a matchbox?

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

What happens when a catalyst is added to a reaction?

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Classify the following day to day activities based on chemical reactions by physical contact, solutions of reactants, heat, light, electricity and catalyst.

Silver ornaments become black on exposure to air for a long time.

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

When dry wood comes into contact with fire, it burns with the help of oxygen to form _____, which is given out as smoke.

EASY

Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Cotyledons are also called-

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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact

Define a chemical reaction.

MEDIUM

Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact