Balance the chemical equation

__H2O -> __ H2 + __ O2

2 H₂O → 2 H₂ + 1 O₂

Explanation:

There are 2 hydrogen atoms on both the sides of the equation. However there is 1 oxygen atom on the left side and 2 oxygen atoms on the right side. So we multiply the 1 atom with 2 to get two oxygen atoms. The equation would look like this:

2 H₂O → 1 H₂ + 1 O₂

Now if you check whether both the sides has equal number of elements, on the left side hydrogen has 4 hydrogen atoms and the right side has 2. Therefore we multiply it with 2 because that gives 4. Thus the equation is balanced.

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.