THCa (Tetrahydrocannabinolic acid) converts to THC (Tetrahydrocannabinol) through thermal decarboxylation, losing a carboxyl group (CO₂):
This reaction removes 44.01 g/mol of CO₂ from each mole of THCa (358.47 g/mol), producing THC (314.46 g/mol).
The conversion ratio is based on the molecular weights of THC and THCa:
This means that 1g of THCa produces approximately 0.8773g of THC when fully decarboxylated.
Completion is calculated based on the observed weight loss compared to the expected CO₂ loss:
Where the expected CO₂ loss is:
Based on the completion percentage, we can calculate the remaining compounds:
The conversion rate measures how much THC is produced per unit time:
The average conversion rate over the entire session is:
Weight loss provides an accurate, real-time measurement of decarboxylation progress because:
1. CO₂ is the only volatile compound lost during decarboxylation
2. The weight loss is directly proportional to THCa conversion
3. It's non-invasive and doesn't require sampling