Chemistry
Calculate relative molecular mass of
(a) ZnCO3
(b) CaSO4
[Zn = 65, S = 32, O = 16, Ca = 40, C = 12]
Answer
(a) Relative Molecular Mass of ZnCO3:
Molecular wt. of ZnCO3 = At. wt. of Zn + At. wt. of C + 3(At. wt. of O)
= 65 + 12 + 3(16)
= 65 + 12 + (48)
= 65 + 60
= 125
Hence, Relative Molecular Mass of ZnCO3 = 125
(b) Relative Molecular Mass of CaSO4:
Molecular wt. of CaSO4 = At. wt. of Ca + At. wt. of S + 4(At. wt. of O)
= 40 + 32 + 4(16)
= 40 + 32 + 64
= 136
Hence, Relative Molecular Mass of CaSO4 = 136
Related Questions
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(a) Ammonia first reacts with chlorine to give hydrogen chloride and nitrogen.
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(a) Ozone first decomposes to give molecular oxygen & nascent oxygen.
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- Reaction of excess ammonia with chlorine – Ammonia as a reducing agent
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(b) calcium nitrate[Ca = 40 , Cl = 35.5 , N = 14 , O = 16]
Match the names of ions and radicals from 1 to 10 with their correct answer from A to Q.
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