Question

find number of particles present in 5 grams of sodium chloride

Answer 1

You need to find the mass of NaCl.

Mass of Na = 23 g

Mass of Cl = 35.5 g

Total mass = 23 + 35.5 = 58.5 g

From equation,

Number of moles (N) = (Given Mass/Total Mass) x Avogadro's Number

Given mass = 5g

----> N =  5/58.5 x 6.022 x 10^23

Hence, N = 5.1 x 10^22 Moles