3 examples of scaled mole conversions

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Sure! Here are three examples of scaled mole conversions involving different substances:

Example 1: Moles of Water to Grams

Problem: How many grams are in 5 moles of water (H₂O)?

  1. Determine the molar mass of water:

    • H (Hydrogen) = 1.01 g/mol × 2 = 2.02 g/mol
    • O (Oxygen) = 16.00 g/mol
    • Total = 2.02 g/mol + 16.00 g/mol = 18.02 g/mol
  2. Conversion to grams: \[ \text{Mass} = \text{moles} \times \text{molar mass} = 5 , \text{moles} \times 18.02 , \text{g/mol} = 90.10 , \text{g} \]

Result: 5 moles of water is 90.10 grams.


Example 2: Moles of Carbon Dioxide to Liters at STP

Problem: How many liters of carbon dioxide (CO₂) are in 2 moles at standard temperature and pressure (STP)?

  1. Use the molar volume of a gas at STP:

    • At STP, 1 mole of gas occupies 22.4 liters.
  2. Conversion to liters: \[ \text{Volume} = \text{moles} \times \text{molar volume} = 2 , \text{moles} \times 22.4 , \text{L/mol} = 44.8 , \text{L} \]

Result: 2 moles of carbon dioxide is 44.8 liters.


Example 3: Moles of Sodium Chloride to Molecules

Problem: How many molecules are in 0.5 moles of sodium chloride (NaCl)?

  1. Use Avogadro's number:

    • Avogadro’s number = \( 6.022 \times 10^{23} \) molecules/mol.
  2. Conversion to molecules: \[ \text{Number of molecules} = \text{moles} \times \text{Avogadro's number} = 0.5 , \text{moles} \times 6.022 \times 10^{23} , \text{molecules/mol} = 3.011 \times 10^{23} , \text{molecules} \]

Result: 0.5 moles of sodium chloride contains \( 3.011 \times 10^{23} \) molecules.


These examples illustrate how mole conversions can be scaled based on the required units (grams, liters, or molecules) using the appropriate formulas and constants.