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What is one key difference between a chemical reaction with a catalyst and one without?

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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?
EASY
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?
EASY
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?
MEDIUM
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?
MEDIUM
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?
MEDIUM
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?
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.

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

MEDIUM
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-
EASY
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
A chemical change is _____, _____ and produces _____. (temporary/permanent, reversible/Irreversible, new substance/no new substance)
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Science>Chemistry>Changes Around Us>Chemical Reactions Based on Physical Contact
What can increase the surface area of a solid reactant in a reaction?