How many grams are in 0.0864 mol of sodium? How many grams are in 0.0864 mol of sodium?
The correct answer and explanation is:
Correct Answer:
1.99 grams
Explanation:
To determine the number of grams in a given number of moles, use the formula:
Mass (g) = Moles × Molar Mass
Sodium (Na) has a molar mass of approximately 22.99 g/mol. This means that 1 mole of sodium atoms weighs 22.99 grams.
In this case, the number of moles is given as 0.0864 mol. To find the mass: Mass=0.0864 mol×22.99 g/mol=1.987536 g\text{Mass} = 0.0864 \text{ mol} \times 22.99 \text{ g/mol} = 1.987536 \text{ g}
Rounded to three significant figures, the result is: 1.99 grams\boxed{1.99 \text{ grams}}
This calculation shows the direct relationship between moles and mass through the molar mass of the element. Molar mass is obtained from the periodic table and represents the mass of one mole of atoms or molecules of a substance. For sodium, its atomic mass is 22.99, and since sodium is an element and not a compound, the molar mass is the same.
The mole is a standard unit in chemistry that represents a fixed number of particles, specifically 6.022 × 10²³ atoms, molecules, or ions. This large number allows chemists to work with amounts of substances that are practical and measurable in the lab.
Using molar mass helps convert between the amount of a substance (in moles) and its actual weight (in grams). In this case, multiplying the small quantity of 0.0864 mol by the molar mass of sodium gives a corresponding small mass of 1.99 grams, which could easily be measured in a laboratory using a balance.