Molar mass of KCl = 39 + 35.5 = 74.5 g/mol. Number of moles = mass/molar mass = 1500 g / 74.5 g/mol ≈ 20.1 moles.
Questions & Step-by-step Solutions
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Q
Q: How many moles are in 1.5 kg of KCl?
Solution: Molar mass of KCl = 39 + 35.5 = 74.5 g/mol. Number of moles = mass/molar mass = 1500 g / 74.5 g/mol ≈ 20.1 moles.
Steps: 5
Step 1: Find the molar mass of KCl. Add the atomic mass of potassium (K) which is 39 g/mol and chlorine (Cl) which is 35.5 g/mol. So, 39 + 35.5 = 74.5 g/mol.
Step 2: Convert the mass of KCl from kilograms to grams. Since 1 kg = 1000 g, 1.5 kg = 1.5 * 1000 = 1500 g.
Step 3: Use the formula to find the number of moles. The formula is: Number of moles = mass (in grams) / molar mass (in g/mol).
Step 4: Plug in the values: Number of moles = 1500 g / 74.5 g/mol.
Step 5: Calculate the result: 1500 divided by 74.5 is approximately 20.1 moles.
