A lead atom has a mass of 3.4 * 10 ^ - 22 * g How many lead atoms are in a cube of lead that has a volume of 4.50 cm^ 3 the density of lead is 11.3g/cm^ 3
really? a tiny fraction of one atom?
4.50cm^3 * 11.3g/cm^3 * 1atom/(3.4*10^-22 g)
= (4.5*11.3)/(3.4*10^-22)
= 1.50*10^23 atoms
To find the number of lead atoms in a given volume, we need to follow a few steps.
Step 1: Calculate the mass of the lead cube
To find the mass of the lead cube, we need to use its density and volume. The formula for calculating mass is:
Mass = Density × Volume
Given that the density of lead is 11.3 g/cm³ and the volume is 4.50 cm³, we can substitute those values into the formula:
Mass = 11.3 g/cm³ × 4.50 cm³
= 50.85 g
So, the mass of the lead cube is 50.85 g.
Step 2: Convert mass to the number of moles
To convert the mass of lead to the number of moles, we need to use the molar mass of lead. The molar mass of an element is the mass of one mole of the element. The molar mass of lead (Pb) is 207.2 g/mol.
Number of moles = Mass / Molar mass
Number of moles = 50.85 g / 207.2 g/mol
≈ 0.2455 mol
So, the number of moles of lead in the cube is approximately 0.2455 mol.
Step 3: Convert moles to the number of atoms
To convert moles to the number of atoms, we need to use Avogadro's number. Avogadro's number is the number of atoms in one mole of an element and is approximately 6.022 × 10²³ atoms/mol.
Number of atoms = Number of moles × Avogadro's number
Number of atoms = 0.2455 mol × 6.022 × 10²³ atoms/mol
≈ 1.477 × 10²³ atoms
So, there are approximately 1.477 × 10²³ lead atoms in the given lead cube.