What is the number of hydrogen atoms in 5 moles of water?
Correct answer: B. 6.023 x 10^24
- A. 3.0115 x 10^24
- B. 6.023 x 10^24
- C. 6.023 x 10^23
- D. 5.0 x 10^23
Explanation
5 moles of water contains 5 moles of H2, therefore contains 10 moles of H atoms.The number of atoms in one mole of a substance is given by Avogadro's constant, which is 6.02x1023.Thus the number of hydrogen atoms in 5 moles of water = 10x(6.02x1023) = 6.02x1024 H atoms.
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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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