Answer:
0.78× 10 ²³ molecules
Step-by-step explanation:
Given data:
Mass of pyridine = 10.35 g
Number of molecules = ?
Solution:
Number of moles of pyridine:
Number of moles = mass/molar mass
Number of moles = 10.35 g/ 79.1 g/mol
Number of moles = 0.13 mol
Number of molecules;
1 mole contain 6.022× 10 ²³ molecules
0.13 mol × 6.022× 10 ²³ molecules / 1mol
0.78× 10 ²³ molecules