The valencies(or charges) of some of the ions are given below:

Ion Valency(charge) Ion Valency(charge)

Sodium ion 1+ Nitrate ion 1-

Copper ion 2+ Sulphide ion 2-

Using this information, write down the formula of sodium sulphide.

Important Questions on Atoms and Molecules

EASY

9th CBSE

IMPORTANT

Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Short Answer Type Questions>Q 27

The valencies(or charges) of some of the ions are given below:

Ion Valency(charge) Ion Valency(charge)

Sodium ion 1+ Nitrate ion 1-

Copper ion 2+ Sulphide ion 2-

Using this information, write down the formula of copper nitrate.

EASY

9th CBSE

IMPORTANT

Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Short Answer Type Questions>Q 28

Explain the formation of (i) sodium ion and (ii) chloride ion, from their respective atoms giving the number of protons and number of electrons in each one of them. What is the reason for positive charge on a sodium ion and negative charge on a chloride ion?

MEDIUM

9th CBSE

IMPORTANT

Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Short Answer Type Questions>Q 29

Write the symbols/formulae of two simple ions and two compound ions( or polyatomic ions).

MEDIUM

9th CBSE

IMPORTANT

Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Short Answer Type Questions>Q 29

An element Y has a valency of 4. Write the formula for its chloride.

EASY

9th CBSE