what is the number of moles in 40gm Nacl
The correct answer and explanation is:
To calculate the number of moles in 40 g of sodium chloride (NaCl), follow these steps:
- Find the molar mass of NaCl: The molar mass of NaCl is the sum of the atomic masses of sodium (Na) and chlorine (Cl).
- Sodium (Na) has an atomic mass of 23 g/mol.
- Chlorine (Cl) has an atomic mass of 35.5 g/mol.
- Use the formula to calculate moles: The number of moles can be calculated using the formula: Moles=Mass of substance (g)Molar mass (g/mol)\text{Moles} = \frac{\text{Mass of substance (g)}}{\text{Molar mass (g/mol)}} In this case, the mass of NaCl is 40 g, and the molar mass is 58.5 g/mol. Substituting these values into the formula gives: Moles of NaCl=40 g58.5 g/mol≈0.6836 moles\text{Moles of NaCl} = \frac{40 \, \text{g}}{58.5 \, \text{g/mol}} \approx 0.6836 \, \text{moles}
So, there are approximately 0.684 moles of NaCl in 40 g.
Explanation:
A mole is a standard unit in chemistry that represents a specific number of particles, 6.022 x 10²³ (Avogadro’s number). The molar mass of a compound tells you how many grams of that substance correspond to one mole. In this case, one mole of NaCl weighs 58.5 g. When you have 40 g of NaCl, it is less than one mole, and so you use the formula to convert the mass to the number of moles. By dividing the mass of NaCl by its molar mass, you can find how many moles are present in any given mass of the compound.