Fill in the Blanks :-
1. Al₂O₃ is the chemical formula of ______________.
2. The substances produced in a chemical reaction are called ______________.
3. The reaction in which an acid combines with a base to form salt and water is called ____________.
4. A dilute solution of copper sulphate can be changed to saturated solution by ______________.
5. A _____________ represent the name of an element.
6. An _____________ has similar kind of atoms.
7. Heat is absorbed during _____________ reactions and evolved during _____________ reactions.
8. ______________ is the smallest particle of a compound and of an element.
9. ________________ can be separated into its constituents by physical methods.
10. ____________ is liquid metal used in thermometer.
_______________________________________
True or False :-
1. Neutralisation means salts combine with water.
2. The number of atoms of an element in a molecule is called atomicity
3. Zinc can displace iron from ferrous sulphate solution.
4. Atoms take part in chemical reactions.
5. The salt used by us is recovered from water try evaporation and crystallization.
6. Crystallisation is an irreversible change.
7. Rusting of iron is a reversible change.
8. A precipitate is produced when an insoluble substance is formed during a chemical reaction.
Answers
Answer- The above questions are from the chapters 'Acids, Bases and Salts' and 'Physical and Chemical Changes'.
Given question: Fill in the Blanks :-
1. Al₂O₃ is the chemical formula of ______________.
2. The substances produced in a chemical reaction are called ______________.
3. The reaction in which an acid combines with a base to form salt and water is called ____________.
4. A dilute solution of copper sulphate can be changed to saturated solution by ______________.
5. A ____________ represents the name of an element.
6. An _____________ has similar kind of atoms.
7. Heat is absorbed during _____________ reactions and evolved during _____________ reactions.
8. ______________are the smallest particles of a compound and of an element.
9. ________________ can be separated into its constituents by physical methods.
10. ____________ is liquid metal used in thermometer.
True or False :-
1. Neutralization means salts combine with water.
2. The number of atoms of an element in a molecule is called atomicity
3. Zinc can displace iron from ferrous sulphate solution.
4. Atoms take part in chemical reactions.
5. The salt used by us is recovered from water try evaporation and crystallization.
6. Crystallization is an irreversible change.
7. Rusting of iron is a reversible change.
8. A precipitate is produced when an insoluble substance is formed during a chemical reaction.
Answer: Fill in the Blanks :-
1. Al₂O₃ is the chemical formula of Aluminium Oxide.
2. The substances produced in a chemical reaction are called products.
3. The reaction in which an acid combines with a base to form salt and water is called neutralization reaction.
4. A dilute solution of copper sulphate can be changed to saturated solution by adding more copper sulphate crystals.
5. A chemical formula represents the name of an element.
6. An element has similar kind of atoms.
7. Heat is absorbed during endothermic reactions and evolved during exothermic reactions.
8. A molecule and an atom are the smallest particles of a compound and of an element.
9. Mixture can be separated into its constituents by physical methods.
10. Mercury is liquid metal used in thermometer.
True or False :-
1. False
2. True
3. True
4. True
5. True
6. False
7. False
8. True