Here's how to calculate the total number of atoms in the molecule C₁₂H₂₂O₁₁ (sucrose):

1. Identify the subscripts: The subscripts in the chemical formula tell you how many atoms of each element are present in one molecule:

* C₁₂ = 12 carbon atoms

* H₂₂ = 22 hydrogen atoms

* O₁₁ = 11 oxygen atoms

2. Add the subscripts: 12 + 22 + 11 = 45 atoms

Therefore, there are 45 atoms in one molecule of sucrose (C₁₂H₂₂O₁₁).