Table of contents

Word equation

ethanol + formaldehyde → water + acetone

Input interpretation

CH3CH2OH + HCHO → H2O + CH3COCH3

Ethanol formaldehyde water acetone

Balanced equation

Balance the chemical equation algebraically: 

CH3CH2OH + HCHO → H2O + CH3COCH3

Add stoichiometric coefficients, c1, to the reactants and products:

c1CH3CH2OH + c2HCHO → c3 H2O + c4 CH3COCH3

Set the number of atoms in the reactants equal to the number of atoms in the products for C, H and O:

C: 2c1 + c2 = 3c4

 H: 6c1 + 2c = 2c3 + 6c4 

O: c1 + c2 = c3 + c4

Since the coefficients are relative quantities and underdetermined, choose a coefficient to set arbitrarily. To keep the coefficients small, the arbitrary value is ordinarily one. For instance, set c1 = 1 and solve the system of equations for the remaining coefficients:

c1=1 c2=1

c3 = 1 c4=1

Substitute the coefficients into the chemical reaction to obtain the balanced

equation:

Answer:

CH3CH2OH + HCHO → H2O + CH3COCH3