CBSE Class 9 Chemistry Atoms and Molecules
- (B) An element X has 17 protons and 18 electrons. (a) what is the valency of X? (b) find the number of neutrons in X? (c) What is the mass number of X?
- how is protons mass when compared to electron
- what is the Mass of electron
- Why hydrogen atom does not have neutrons
- name and write the formula of atleast 20 elements of everyday use
- the ratio by mass of nitrogen and hydrogen in ammonia is 14:3 . calculate the ratio by number of atoms of elements in ammonia molecule .
- Assertion reason (A) phosphate ion is a polyatomic anion (R) in phosphate anion 5 atoms are present
- calculate the formula unit mass of CaCl2
- Calculate the molecular mass of h20
- find molar mass of sodium carbonate
