I believe it would be the last one because you can use the molar mass of HCl to find the number of moles, then use Avogadro’s number to find the number of atoms
Hope this helps!
The atomic mass of platinum rounded to the nearest whole number is 195.
The atomic mass of an element refers to the weighted average of the masses of all the isotopes of the element. The mass number is the sum of the number of protons and neutrons in the nucleus.
Looking at the question, it is clear that the atomic mass of platinum rounded to the nearest whole number is 195.
Learn more about atomic mass: brainly.com/question/5566317
the answer is a chemical element
The answer is it tends to be more negative down a group. This is because as you go down the periodic table, the elements have more electron shells in their atoms. This makes the outermost shells less attracted to the nucleus due to their greater distances from the nucleus. Therefore, these shells are less likely to attract electrons (hence lower electron affinity) and are even more likely to lose electrons from their outer electron orbits.
It is the beginning stage