Chlorine has 7 valence electrons
The answer is Cartography.
The Group 3A metals have three valence electrons in their highest-energy orbitals (ns2p1). They have higher ionization energies than the Group 1A and 2A elements, and are ionized to form a 3+ charges. The Group 3A metals are silvery in appearance, and like all metals are good conductors of electricity.
Answer:
B- why or how because any scientist deals with matter it's relationships ,properties and its composition which can be inferred from the questions why and how
Answer:
C. The first ionization energy decreases because the outermost
electron is farther from the nucleus.
Explanation:
Ionization energy trend along group:
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus.
Ionization energy trend along period:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required.
