117.0g of NaCl have
Correct answer: A. 12.04 x 10^23 Formula unit of NaCl
- A. 12.04 x 10^23 Formula unit of NaCl
- B. 12.04 x 10^22 Formula unit of NaCl
- C. 12.04 x 10^23 Molecules of NaCl
- D. 6.023 x 10^23 Molecules of NaCl
Explanation
Option A is correct.To calculate the number of formula units of NaCl in 117.0g of NaCl, we can use the following steps: Calculate the number of moles of NaCl in 117.0g of NaCl. Multiply the number of moles of NaCl by Avogadro's number (6.022 x 10^23 atoms/mol) to get the number of formula units of NaCl. Step 1: Calculate the number of moles of NaCl in 117.0g of NaCl. The molar mass of NaCl is 58.5g/mol. This means that 1 mole of NaCl weighs 58.5g. Number of moles of NaCl = mass of NaCl / molar mass of NaCl Number of moles of NaCl = 117.0g / 58.5g/mol Number of moles of NaCl = 2.0 moles Step 2: Multiply the number of moles of NaCl by Avogadro's number to get the number of formula units of NaCl. Number of formula units of NaCl = number of moles of NaCl * Avogadro's number Number of formula units of NaCl = 2.0 moles * 6.022 x 10^23 atoms/mol Number of formula units of NaCl = 1204 x 10^23 formula units Therefore, 117.0g of NaCl have 12.04 x 10^23 formula units of NaCl.
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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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