How much ethanol is required to react with 25 g of potassium?

To solve, we write down the equation of the process:

Xr -? m = 25 g

2С2Н5ОН + 2K = 2C2H5OK + H2 – substitutions, obtained potassium ethylate, hydrogen.
Calculations by formulas:
M (C2H5OH) = 46 g / mol;

M (K) = 39.1 g / mol;

Y (K) = m / M = 25 / 39.1 = 0.64 mol;

Y (C2H5OH) = 0, 64 mol since the amount of substances is 2 mol.

3. Find the mass of the original substance:

m (C2H5OH) = Y * M = 0.64 * 46 = 29.4 g

Answer: the mass of ethanol is 29.4 g