Question

15. Chlorophyll, the green colouring matter of plants
responsible for photosynthesis, contains 2.68%
of magnesium by mass. Calculate the number
of magnesium atoms in 2.00 g of chlorophyll
xygen​

Answer 1

2.68g Mg in 100g chlorophyll

moles of Mg = Given mass/Molar mass = 2.68/24 = 0.11 mol

No. of Mg atoms inn 100g chlorophyll = 0.11 x 6.02 x 10^23 = 0.66 x 10^23

2g chlorophyll contains = 0.66 x 2 x10^23/100 = 1.32 x 10^21 atoms of Mg