Question 8 — Determine the formula unit mass - Questions at the end of the chapter - Chapter 9 - Atomic Foundations of Matter (Exploration)

Last updated at July 3, 2026 by

Question 8
Determine the formula unit mass of the following substances. (i) Ammonium nitrate (NH₄NO₃), used as a nitrogen fertiliser, which is essential for plant growth. (ii) Phosphoric acid (H₃PO₄), used to make phosphate fertiliser and detergents. (iii) Sodium hydrogencarbonate (NaHCO₃), used to relieve acidity and helps in digestion.
View Answer Hide Answer
  • (i) NH₄NO₃ = 14 + 4 + 14 + 48 = 80 u .
  • (ii) H₃PO₄ = 3 + 31 + 64 = 98 u .
  • (iii) NaHCO₃ = 23 + 1 + 12 + 48 = 84 u .

Atomic masses: H=1, C=12, N=14, O=16, Na=23, P=31.

Formula Unit Masses NH4NO3 equals 80 u H3PO4 equals 98 u NaHCO3 equals 84 u
Back to: 9.8 Formula Unit Mass of Ionic Compounds
Remove Ads Share on WhatsApp
CA Maninder Singh's photo - Co-founder, Teachoo

Made by

CA Maninder Singh

CA Maninder Singh is a Chartered Accountant with 16+ years of practical experience and 20+ years of teaching experience. At Teachoo, he simplifies Accounts, Tax and GST with step-by-step examples so students can apply concepts confidently in exams and real life.

For an uninterrupted learning experience, students can use Teachoo Black to remove ads and focus better.