Answer:
Explanation: I don't know
Isotopes of an element have same atomic number (number of protons) but vary in the mass number (number of neutrons). The chemical reactivity of an element is not affected by the change in mass number. So, for stable isotopes of Oxygen, (Oxygen-16, Oxygen-17 and Oxygen-18) the biochemical pathway of oxygen breathed in during respiration remains unaffected even with different isotopes. Only the radioactive isotopes of oxygen when breathed in may cause serious health hazards as they emit radiations that may damage the internal organs in the body.
Answer: This is called moles
Explanation: This is described to be the number of molecules, atoms or ions in a substance :)
Chromium (Cr): 2, 8, 8, 6
Copper (Cu): 2, 8, 8, 11
Chromium+2 (Cr+2): 2, 8, 8, 4 (if the ion retains a positive charge then the amount of electrons will decrease)
Copper+2 (Cu+2): 2, 8, 8, 9
Manganese+2 (Mn+2): 2, 8, 8, 5
Matter is everything around you, atoms and molecules are all composed of matter.
