Fill in the blanks (a) In a chemical reaction, the sum of the masses of the reactants and products remains unchanged. This is called ————. (b) A group of atoms carrying a fixed charge on them is called ————. (c) The formula unit mass of Ca3 (PO4) 2 is ————. (d) Formula of sodium carbonate is ———— and that of ammonium sulphate is ————.
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
Answers
- Law of conservation of mass
- Ions
- 310
Explanation
3 × atomic mass of Ca+ 2 × atomic mass of phosphorus + 8 × atomic mass of oxygen) = 310
3 × 40 + 2 × 31 + 8 × 16 = 120 + 62 + 128 = 310
- Na2 CO3 and (NH4) 2 SO4
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