Question

i) State six postulates of dalton's atomic theory.
ii) An element has valancy 3. Write the formula of its oxide.

Answer 1

Answer:

1.All matter consists of indivisible particles called atoms.

2 .Atoms of the same element are similar in shape and mass, but differ from the atoms of other elements.

3.Atoms cannot be created or destroyed.

4.Atoms of different elements may combine with each other in a fixed, simple, whole number ratios to form compound atoms.

5.Atoms of same element can combine in more than one ratio to form two or more compounds.

6.The atom is the smallest unit of matter that can take part in a chemical reaction.

Answer

X has valency 3 and oxide ion has valency 2

So, the formula of oxide will be X2 O3

Answer 2

Answer :

1) State six postulates of dalton's atomic theory.

• All matter consists of indivisible particles called atoms.

• Atoms of the same element are similar in shape and mass, but differ from the atoms of other elements.

• Atoms cannot be created or destroyed.

• Atoms of different elements may combine with each other in a fixed, simple, whole number ratios to form compound atoms.

• Atoms of same element can combine in more than one ratio to form two or more compounds.

• The atom is the smallest unit of matter that can take part in a chemical reaction.

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2) An element has valancy 3. Write the formula of its oxide.

• The chemical formula of the given oxide is X2O3.

• Explanation: The valency of element X is 3 and the valency of oxygen( in oxide) is 2.