Is it true non-metals can form cations when combined with metals and anions when combined with other non-metals.

The given statement is true.

Explanation:

An ion is formed when a neutral atom looses or gains electrons.

Metals are the elements which have a tendency to loose electrons and thus they form cations. Example: Lithium will loose 1 electron to form ion.

Non-metals are the elements which have a tendency to gain electrons and thus they form anions. Example: Chlorine will gain 1 electron to form ion.

Ionic compound is formed by the complete transfer of electrons from 1 atom to another atom. The cation is formed by the loss of electrons by metals and anions are formed by gain of electrons by non metals.

Hence, the given statement is true.

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.