Answer:
Aluminum; [Ne]3s²3p¹
Arsenic; [Ar]3d¹⁰4s²4p³
Explanation:
<em>Aluminum</em>
From the periodic table, we have that aluminum, Al, is located in period 3, and group 3A of the periodic table
Therefore, the noble gas that comes before aluminum in the periodic table is neon Ne
The electronic configuration of aluminum is 1s²2s²2p⁶3s²3p¹
The electronic configuration of neon is 1s²2s²2p⁶
Therefore, the electronic configuration of aluminum in noble gas notation (Ne) is therefore;
[Ne]3s²3p¹
<em>Arsenic</em>
Arsenic is located after argon, Ar on the periodic table
The electronic configuration of arsenic is 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p³
The electronic configuration of argon is 1s²2s²2p⁶3s²3p⁶
The electronic configuration of arsenic in noble gas notation (Ar) is given as follows;
[Ar]3d¹⁰4s²4p³
1 mol of Silicon = 28.0855 g (in average)
then
1 mol = 6.022*10^23 atoms
then
28.0855/(6.022*10^23) g/atom
4.66381*10^-23 g per atom
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.
