Answer;
= 4.81 × 10^22 particles
Step-by-step explanation;
The molar mass of Cr2(SO3)3 is 344.18 g
1 mole of a substance contains 6.02 10^23 particles
But; 1 mole of chromium (iii) sulfite = 344.18 g
Therefore;
344.18 g = 6.02×10^23 particles
27.5 g = ?
Hence;
= (27.5 × 6.02 × 10^23)/344.18
= 4.81 × 10^22 particles