Sodium (na) , atomic number 11, has a tendency to lose an electron in the presence of chlorine. after losing the electron, na will have protons in its nucleus

The atomic number is equal to number of protons present in the nucleus of an atom or vice-versa. For any atom, there is no change in number of protons either by adding or removal of electron.

Since, sodium is a metal, it has tendency to lose electron in the presence of non-metal i.e. chlorine. Thus, after lose of an electron, there is no change in the number of protons or number of protons will remain same.

Therefore, atomic number of metal is 11 which is also equal to the number of protons implies sodium will have 11 protons in its nucleus.

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.