Fe atoms are in .256 mole of Fe?
Kr atoms are in 3.87 g of Kr?
2007-03-15 09:37:21 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
0.256 mol Fe x (6.02 x 10^3) = atoms Fe
3.87 g Kr divided by mass of Kr = moles Kr
moles Kr x (6.02 x 10^23) = atoms Kr
2007-03-15 09:42:39 · answer #1 · answered by physandchemteach 7 · 0⤊ 0⤋
.256* 6.02*10^23 = number of atoms in .256mole of Fe
Divide 3.87g of Kr by it's molar mass (it is the same as the atomic mass that is listed on a periodic table). Then multipy that by 6.02*10^23 to get the number of atoms in 3.87g of Kr.
2007-03-15 17:08:39 · answer #2 · answered by dancemusicalsdance 2 · 0⤊ 0⤋
atoms=moles*6.02*10^23
atoms=.256*6.02*10^23
about 1.54x10^23 atoms
moles=mass/atomic mass
3.87/83.8=0.046moles
atoms=0.046*6.02*10^23
atoms= about 2.8x10^22
2007-03-15 16:44:38 · answer #3 · answered by MLBfreek35 5 · 0⤊ 0⤋