1. Ionization energy is the energy needed to remove an electron from an atom. We can use the periodic table to predict ionizatio
n energy for an element. • State and explain the trend for ionization energy as you move from left to right across a period.
• State and explain the trend for ionization energy as you move down a group.
(5 points)
2. A neutral atom of phosphorus has 15 electrons. Explain why the electron configuration below is not the correct configuration for a neutral atom of phosphorus in its ground state.
1s2 2s2 2p6 3s2 3p2 4s1
3. Find rubidium, magnesium, and aluminum on the periodic table. Fill in the table below based on the locations of these metals on the periodic table. Be thorough in filling in the far right column!
left to right column: Element Symbol Group number Number of valence electrons General reactivity of the metal with an explanation for this reactivity based on the number of valence electrons
Up to down column:
Rubidium
Magnesium
Aluminum
Ionization energy increases from left to right because the left wants to lose elctrons and the right wants to gain electron
As you go a group it is easier lose lose because the electrons are farther away from the nucleus and there is less attraction from the positive charges.
It should be 3p3. the p level can hold 6 electrons
Rubidium group 1, 1 valence electrons very reactive
Three half lives corresponds to (12)3 . So a 18 quantity of the original isotope is retained. And the percentage of quantity of a radioactive material that remains after 5 half-lives will be . ∴NN0×100=10032=3.125.
