Un elemento posee dos isótopos cuyos números de masa suman 68 y la semisuma de sus neutrones es 19. Determine el grupo de este elemento en la Tabla Periódica Actual.

The element belongs to group 15 of the present periodic table

Explanation:

Isotopes have the same proton number, what differs is that they have different number of neutrons.

Now since the half-sum of their neutrons is 19, the total number of neutrons would be 19 * 2 = 38 neutrons.

Also, their masses add up to be 68, since the total mass equals sum of neutrons and sum of protons, this means that the total number of protons is 68-38 = 30

Since this is equal in both isotopes, this means that the proton number of the element is 30/2 = 15

The atomic number is the number of protons in the nucleus of an atom. Since the atomic number is 15, this element is phosphorus and it belongs to group 15 of the present periodic table

step-by-step explanation:

whole numbers, zero or greater

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.