Question

Calculate the mass of 500. atoms of iron (fe)

Answer 1

4.638*10^-20g

Step-by-step explanation:

1 mole of any substance is equal to the molar mass.

1 mole of any substance is equal to Avogadro's number

6.02*10^23 atoms = 1 moles

500 atoms = x mole

X = (500*1) / 6.02*10^23

X = 8.305*10^-22 mole.

1 mole = molar mass

Molar mass of Fe = 55.845g/mol

1 mole = molar mass= 55.845

8.305*10^-22 = y g

Y = (55.845 * 8.305*10^-22) / 1

Y = 4.638*10^-20g

Answer 2

The atomic mass of an element is the total mass of the particles present in an atom of the element. The atom posses the nucleus, which is surrounded by electrons. The electrons posses one unit negative charge which neutralizes the positive charge of the nucleus coming from the protons. Now for a neutral atom the number of electrons, protons and neutrons will be same. Thus the atomic mass will be equivalent to the mass of the number of proton, neutron and electrons present.

Mass of one mole i.e, 6.023 X 10²³ atoms is 55.84 g, so mass of 500 atoms will be=
`(55.84 X 500)/(6.023 X 10^(23) )` g= 4.63 X 10⁻²⁰ g.