what is chemical reaction? Name four conditions required for chemical reaction with an examples of each.

two reactants are critical requirement essental for reation. whereas precipitate is defined is an insoluble material produced when two aqueous solutions react with each other chemically.

 a process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in physical form or a nuclear reaction.

Explanation: hope this helps

particle   p is an electron and particle q is a neutron

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.