F because it NEVER forms any cations in chemical reactions
Answer:
the number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.
There are 30 protons and 39 neutrons in the nucleus.
This must me the isotope of an element with an atomic mass close to 69 u.
The only candidates are Zn and Ga.
Zn has a zinc-69 isotope with mass 68.926 u.
Ga has a gallium -69 isotope with mass 68.925 u.
The isotope is probably

.
It has 30 protons and 39 neutrons.
Hey there!
A mole is measured in atoms, molecules, particles. It's kind of a loose sort of measurement, just unit of the substance.
Since there is a ratio of 1 to 1 nitrogen to oxygen, there will be the same amount of molecules as atoms of nitrogen.
2.25 moles of NO gas are formed from 2.25 moles of nitrogen.
Hope this helps!