unit 3

Question 1

what group are alkaili metals

Answer 1

group 1

Question 2

what group are alkali earth metals

Answer 2

group 2

Question 3

what group are halogens

Answer 3

group 17

Question 4

what group are noble gases

Answer 4

group 18

Question 5

who made the first periodic table

Answer 5

Dimitri Mendeleev

Question 6

how did Dimitri Mendeleev organize the periodic table

Answer 6

by atomic mass

Question 7

who revised the periodic table

Answer 7

Henry Moseley

Question 8

how did Henry Moseley organize the Periodic table

Answer 8

by atomic number

Question 9

what are horizontal rows of the periodic table called

Answer 9

periods

Question 10

what are vertical columns of the periodic table called

Answer 10

groups or families

Question 11

what are valence electrons

Answer 11

outermost electrons occupying the highest energy level

Question 12

what is shielding

Answer 12

inner layer electrons occupying lower energy levels

Question 13

what are the trends of shielding

Answer 13

shielding increases from top to bottom, and is constant left to right

Question 14

why does shielding increase from top to bottom

Answer 14

as move down a group another energy level is added

Question 15

why is shielding constant from left to right

Answer 15

because as you move across the periodic table only valence electrons are being added

Question 16

what is atomic radius

Answer 16

the measure of distance between two nuclei of two identical atoms of an element

Question 17

what are the trends of atomic radius

Answer 17

increases from top to bottom, and decreases from left to right

Question 18

why does atomic radius increases from top to bottom

Answer 18

because there are more levels of electrons

Question 19

why does atomic radius decrease from left to right

Answer 19

because more positive nucleus pulls electron clouds tighter

Question 20

what is ionization energy

Answer 20

the energy required to remove an electron from an atom

Question 21

what are the trends of ionization energy

Answer 21

decreases from top to bottom, increases from left to right

Question 22

what does ionization energy decrease from top to bottom

Answer 22

because it is easier to remove an electron from an atom that is shielded and and distance from the nucleus

Question 23

why does ionization energy increase from left to right

Answer 23

because it is harder to take electrons from tightly held electron clouds

Question 24

what is electronegativity

Answer 24

the ability of an atom to attract electrons

Question 25

what are the trends of electronegativity

Answer 25

decreases from top to bottom, increases from left to right

Question 26

what does electronegativity decrease from top to bottom

Answer 26

because of the increase of shielding, nucleus can’t attract an electron as much

Question 27

why does electronegativity increase from left to right

Answer 27

because more positive nucleus attract electrons

Question 28

what is reactivity

Answer 28

the tendency of an element to enter a chemical reaction

Question 29

are alkali metals more reactive up or down the group

Answer 29

down

Question 30

are halogens more reactive up or down the group

Answer 30

up