calculate the mass of 2.50 × 104 molecules of nitrogen gas.
calculate the mass of 2.50 × 104 molecules of nitrogen gas.
Answer: To calculate the mass of 2.50 x 10^4 molecules of nitrogen gas, we first need to determine the molecular weight of nitrogen (N2). The atomic weight of nitrogen is approximately 14.01 g/mol.
The molecular weight of N2 = (2 x atomic weight of N) = (2 x 14.01 g/mol) = 28.02 g/mol
Therefore, one mole of N2 weighs 28.02 grams.
Next, we can use Avogadro’s number to convert the number of molecules to moles:
1 mole of any substance contains 6.022 x 10^23 particles (Avogadro’s number).
Number of moles of N2 = (2.50 x 10^4 molecules) / (6.022 x 10^23 molecules/mol)
Number of moles of N2 = 4.16 x 10^-20 mol
Finally, we can use the molecular weight and the number of moles to calculate the mass of 2.50 x 10^4 molecules of nitrogen gas:
Mass of N2 = (Number of moles of N2) x (Molecular weight of N2)
Mass of N2 = (4.16 x 10^-20 mol) x (28.02 g/mol)
Mass of N2 = 1.17 x 10^-18 g
Therefore, the mass of 2.50 x 10^4 molecules of nitrogen gas is approximately 1.17 x 10^-18 grams.