Fill in the blanks
(a) In a chemical reaction, the sum of the masses of the reactants and products remains
unchanged. This is called __________.
Ans. Law of conservation of mass
(b) A group of atoms carrying a fixed charge on them is called __________.
Ans. Polyatomic ion
(c) The formula unit mass of Ca3(PO4)2 is __________.
Ans. (3 × atomic mass of Ca) + (2 × atomic mass of phosphorus) + (8 × atomic mass of oxygen) = 310
(d) Formula of sodium carbonate is and that of ammonium sulphate is __________.
Ans. Na2 CO3; (NH4)2SO4
