it would need to gain 2 more for it to achieve a stable configuration
the best way to remember this is the noble gasses all have 8 valence electrons and that they are the most stable elements on the periodic table
The majority of the mass of the atom is located in the nucleus. Remember that the nucleus contains both protons and neutrons and therefore, most of the mass of the atom.
Answer:
The further an electron is from the nucleus. the greater its energy level.
Explanation:
When an electron is close to the nucleus, it is at as low an energy level as it can get.
We must put energy into an electron to pull it away from the attraction of a nucleus.
So, electrons that are further from the nucleus are at higher energy levels.
Answer:
The concentration is 0.036 mg/mL
Explanation:
Concentration = 0.2 mM = 0.2/1000 = 2×10^-4 M = 2×10^-4 mol/L × 180,000 mg/1 mol × 1 L/1000 mL = 0.036 mg/mL