Find the mass of glucose, lactic acid required to obtain 50 grams.

Given:
m (CH3-CH (OH) -COOH) = 50 g
To find:
m (C6H12O6) =?
Decision:
1) We draw up the equation of the chemical reaction, let the mass of glucose be x g.
C6H12O6 (fermentation) = 2CH3-CH (OH) -COOH
2) Find the molecular weights of glucose and lactic acid.
M (C6H12O6) = (12 x 6) + (1 x 12) + (16 x 6) = 180 g / mol
M (CH3-CH (OH) -COOH) = 12 + 3 + 12 + 1 + 16 + 1 + 12 + 16 + 16 + 1 = 90 g / mol, since acid 2, then 180 g / mol
3) x g: 180 g / mol = 50 g: 180 g / mol
x = (50 x 180): 180 = 50 g.
Answer: m (C6H12O6) = 50 g.