What is the mass of 1.56 x 1021 atoms of magnesium in grams?

4 Answers

• 1.56×10^21 atoms x (1 mole / 6.022×10^23 atoms) x (24.3 g / mole) = 0.0629 g

• First step, convert the number of atoms into moles (use where 1mole of any atom = 6.022×10^23 atoms):

  1.56×10^21 atoms x (1 mol / 6.022×10^23 atoms ) = 2.59×10^-3 moles

  Final step, convert moles into grams (use the periodic table):

  2.59×10^-3 moles x (24.305g / 1mol) = 0.630 grams Mg

  Good luck!

• To work out the mass of 1.56 x 10^21 atoms of magnesium is grams is split into 2 parts first we have to convert the number of atoms into the number of moles and we do that using this formula

  n=N/NA

  n=number of moles

  N=molecules of substance

  NA=avogadro’s number which is 6.02 x 10^23

  n=(1.56 x10^21) / (6.02 x10^23)=0.00259 mol

  then to work out the mass you have to multiply the number of mole(n)

  by the molar mass(M) of magnesium which is 24.3

  m=n x M

  m=mass

  n=number of moles

  M=molar mass

  m=0.00259 x 24.3= 0.0629g of Mg

  mass of magnesium is 0.0629g

  Hope this answers your question=)

• 1 Mole of Mg is 24.3g.

  (6.02X10^23)X24.3=1.46286X10^25

  1.56X1021/1.46286X10^25=

  1.09X10^-22g