How many moles of sodium chloride are in 42.50 g sodium chloride? (molar mass NaCl = 58.44 g/mole)
The Correct Answer and Explanation is :
To determine how many moles of sodium chloride (NaCl) are in 42.50 grams of NaCl, we use the formula: Moles=Mass (g)Molar mass (g/mol)\text{Moles} = \frac{\text{Mass (g)}}{\text{Molar mass (g/mol)}}
Step 1: Identify the given values
- Mass of NaCl = 42.50 g
- Molar mass of NaCl = 58.44 g/mol
Step 2: Apply the formula
Now, substitute the values into the formula to calculate the number of moles: Moles of NaCl=42.50 g58.44 g/mol\text{Moles of NaCl} = \frac{42.50 \, \text{g}}{58.44 \, \text{g/mol}} Moles of NaCl=0.727 mol\text{Moles of NaCl} = 0.727 \, \text{mol}
Final Answer:
There are 0.727 moles of sodium chloride in 42.50 grams of NaCl.
Explanation:
The relationship between mass and moles is governed by the molar mass of the compound, which tells you how much one mole of the compound weighs. The molar mass of sodium chloride (NaCl) is the sum of the atomic masses of sodium (Na) and chlorine (Cl), which are approximately 22.99 g/mol and 35.45 g/mol, respectively. When you add these together, you get a molar mass of 58.44 g/mol for NaCl.
When you are given the mass of a substance, such as 42.50 grams, you can use the molar mass to convert the mass into moles. This conversion is essential in chemistry because reactions occur in terms of moles of reactants and products. Moles allow you to quantify the number of particles (atoms, ions, or molecules) in a given mass of a substance.
This process of converting grams to moles is a fundamental skill in stoichiometry, which involves calculating the quantities of reactants and products in chemical reactions. In summary, the number of moles of sodium chloride in 42.50 grams is found by dividing the mass by the molar mass, yielding 0.727 moles.