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https://www.careerlauncher.com/cbse-ncert/class-9/Chemistry/CBSE-AtomsandMolecules-Notes.html
Questions
What is an atom?What is the size of atom?
What is atomic mass?
Explain Dalton's atomic theory
What is atomic number?
What is an element?
What are isotopes?
What is mass number?
What is an ion?
What are polyatomic molecules?
What is molecule?
What is molecular mass?
What is mole?
Explain mole concept?
What is molar mass? Unit?
What is law of constant proportion?
What is law of multiple proportion?
What is Avagadro number.
How to write chemical formula of compounds
How does an element differ from a compound? Explain with suitable examples
What does chemical formula of a compound represent?
What is a compound?
What is formula unit mass?
What is a chemical formula?
Write the chemical formula of the following
a. Magnesium chloride
b. Calcium oxide
c. Copper nitrate
d. Aluminum chloride
e. Calcium carbonate
25. Give the names of the element present in the following compound
a. Quick lime.
b. Hydrogen bromide
c. Baking powder
d. Potassium sulphate
26. Convert into mole
a. 12 g of oxygen gas
b. 20g of water
c. 22g of carbon di oxide.