The volume of a gas is doubled while the temperature is unchanged. The pressure of
the gas

The pressure will be halved with respect its initial value

Explanation:

Based on Boyle's law, the pressure exerted by a quantity of an ideal gas is inversely proportional to the volume it occupies if the temperature and remains constant

Thus, if volume of a gas is doubled while the temperature is unchanged, the pressure will be halved with respect its initial value

i think that the answer is c

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.