AP Chemistry worksheet on mole calculations with handwritten answers showing step-by-step solutions for problems involving molar mass, volume at STP, and number of molecules.

A worksheet titled "Mole Calculations - Difficulty Level 3" from South Pasadena AP Chemistry, showing six problems related to mole calculations with handwritten solutions in red ink, including conversions involving moles, molecules, volume at STP, and mass for compounds like CH₄, CO₂, and H₂O.