The answer to this question would be: 2 mol
To answer this question, you need to know the molecular weight of Potassium. Molecular weight determines how much the weight of 1 mol of a molecule has.
Potassium or Kalium molecular weight is 39.1 gram/mol. Then, 78.20gram of potassium should be: 78.20g/ (39.1g/mol)= 2 mol
The answer to this question is theory
