MEDIUM
9th CBSE
IMPORTANT
Earn 100

Calculate the formula mass of the calcium chloride. (Given: Atomic mass of Ca=40 u; Cl=35.5 u) 

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 30

Calculate the formula mass of the sodium carbonate. (Given atomic mass of Na=23u; C=12u; O=16u) 

EASY
9th CBSE
IMPORTANT
Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Multiple Choice Questions (MCQs)>Q 31
The atomic number of an element X is 13. What will be the number of electrons in its ion X3+?
EASY
9th CBSE
IMPORTANT
Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Multiple Choice Questions (MCQs)>Q 32
Which of the following represents a correct chemical formula?
EASY
9th CBSE
IMPORTANT
Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Multiple Choice Questions (MCQs)>Q 33
If the number of electrons in an ion Z3- is 10, the atomic number of element Z will be:
EASY
9th CBSE
IMPORTANT
Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Multiple Choice Questions (MCQs)>Q 34
The anion of an element has:
EASY
9th CBSE
IMPORTANT
Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Multiple Choice Questions (MCQs)>Q 35
A particle X has 17 protons, 18neutrons and 18 electrons. This particle is most likely to be: 
EASY
9th CBSE
IMPORTANT
Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Multiple Choice Questions (MCQs)>Q 36
An element which can exhibit the valencies of 2, 4 and 6 can be:
EASY
9th CBSE
IMPORTANT
Science for Ninth class Part 2 Chemistry>Chapter 3 - Atoms and Molecules>Multiple Choice Questions (MCQs)>Q 37
The atomic number of an element E is 16. The number of electrons in its E2- will be: