Question

Chlorophyll contains 2.68 of magnesium by mass calculate amount of mg in 2 gms of chlorophyll

Answer 1

Answer:

Mass of Mg in 3 gm chlorophyll =3×

100

2.68

=0.0804 gm

Moles of Mg=

24

0.0804

=3.35×10

−3

moles

Number of Magnesium atoms =3.35×10

−3

×6.023×10

23

=2.01×10

21

atoms

Answer 2

Since chlorophyll contains 2.68% Mg therefore weight of Mg in 2g chlorophyll

= 2×2.68/100

= .0536 g

Now Mole of Mg = weight/atomic weight = .0536/24

since 1 mole contains 6.023×10^23 particles

Therefore number of atoms present in .0536/24 mole will be

= (.0536/24) × 6.023×10^23

=1.34 × 10^23 atoms of Mg