Question

20.
21
A chemical compound is always made up of the same element combined together in
fixed proportion by mass. This Law is called me
Define the term atomicity:
Write the correct formulae of the following compound.
1) Hydrogen sulphide.
ii) Aluminum oxide
in) Sodium oxide
Calculate molecular mass of the following compound:-
a) H2O
b) CaCO,
c) HNO,
Copper sulphate reacts with sodium hydroxide to form a blue precipitate of copper
hydroxide and sodium sulphate in an experiment 15.95 gm of copper sulphate
reacted with 8.0 gm of sodium hydroxide to form 9.75 gm of copper hydroxide
and 14.2 gm of sodium sulphate. Which law of chemical combination is illustrated
by this data. Give reason for your choice.
1) State the various postulate of Dalton's atomie theory of matter
ii) State the law of conservation of mass.
Write the separating technique for the following: -
Salt and ammonium chloride
1) Coloured pigments from flower,
Can we separate vinegar and water by using separating funnel. If yes, describe
procedure. If not explain
22​

Answer 1

Answer: atomicity: the number of atoms in the molecules of an element

Explanation:

i) H2S

ii) Al2O3

iii) Na2O