Question

a person adds 2.51g of sugar in order to sweeten his tea the number of carbon atoms added are

Answer 1

sugar is also known as sucrose and has a formula C12H22O11 which will have a molecular mass of 12×12 + 22×1 + 11×16 = 342 gms/mole
now 2.51 grms has 2.51÷342 = 0.007 moles .
1 mole has 22 × 6.023 × 10^ 23 atoms of carbon therefore 0.007 has
0.007×22×6.023×10^23 =9.72×10^22 atoms of carbon