Determine the mass of ethanol obtained by fermentation of 18 g of glucose.

To solve, we write down the equation:
С6Н12О6 = 2С2Н5ОН + 2СО2 – fermentation of glucose occurs with the participation of yeast, ethanol is released;
Let’s calculate the molar mass of glucose, ethanol:
M (C6H12O6) = 180 g / mol;
M (C2H5OH) = 46 g / mol;
Determine the number of moles of glucose if the mass is known:
Y (C6H12O6) = m / M = 18/180 = 0.1 mol.
Let’s make the proportion:
0.1 mol (C6H12O6) – X mol (C2H5OH);
-1 mol                        – 2 mol from here, X mol (C2H5OH) = 0.1 * 2/1 = 0.2 mol;
We find the mass of ethanol by the formula:
m (C2H5OH) = Y * M = 0.2 * 46 = 9.2 g.
Answer: the mass of ethanol is 9.2 g.