M C8H9O2N=8x12+9x1+2x16+14=151g/mol
100 mg=0,1 g paracetamol
a)n=m/M=0,1/151=0,66x10la minus3 moli paracetamol continuti in 100 mg
b)1mol paracetamol contine 6,023x10^23 molecule
0,66x10(-3) contin X molecule
X=0,66x10(-3)x6,023x10^23=3,97518x10^20 molecule
c)1mol paracetamol contine 8x6,023x10^23 atomi de C
0,66 x10 la minus 3 contin Yatomi de C
Y=0,66x10(-3)x8x6,023x10^23=5,28x6,023x10^20 atomi de C