How many oxygen atoms are present in 278g of Hydrated Ferrous Sulphate?(FeSO4.7Hz 0 = 278 any)
Correct answer: B. 6.525 x 10^24
- A. 6.023 x 10^23
- B. 6.525 x 10^24
- C. 2.408 x 10^23
- D. 6.023 x 10^22
Explanation
The chemical formula for hydrated ferrous sulfate is FeSO4·7H2O, which includes 4 oxygen atoms from the sulfate ion (SO4) and 7 oxygen atoms from the 7 water molecules (7H2O), resulting in a total of 11 oxygen atoms per formula unit.Multiplying the number of oxygen atoms by Avogadro's number (6.023 x 1023) gives the total number of oxygen atoms in one mole of the compound: 11 x 6.023 x 1023 = 6.625 x 1024 oxygen atoms.Thus, Option B is correct. Options A, C, and D do not account for the correct total number of oxygen atoms in the compound when multiplied by Avogadro's number, leading to incorrect results.
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About Moles and Avogadro's Number
The mole connects the microscopic number of particles with measurable mass, using Avogadro's number, 6.022 × 10²³ particles per mole. Questions involve molar mass, conversion between mass, moles and particles, percentage composition, empirical and molecular formulas, and distinguishing atoms, molecules, ions and formula units.
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