Cinnabar (HgS) is a prominent ore of mercury. How many grams of mercury are present in 225 g of pure HgS? Molar mass of Hg and S are 200.6 g mol–1 and 32 g mol–1 respectively.
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
Molar mass of HgS = The molar mass of Hg + the molar mass of S
= 200.6 + 32 = 232.6 g mol–1
1molecule of HgS contains 1 atom of Hg
232.6 g of HgS contains 200.6 g of Hg
Therefore, Mass of Hg in 225 g of HgS = 200.6 X 225 = 194.04g
232.6
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