Periodicity

Question 1

Atomic radis

Answer 1

Distance from nucleus to outermost electron

Question 2

Ionic radius

Answer 2

Distance from nucleus to outermost electrons in an ion

Question 3

Electron affinity

Answer 3

Energy released when one mole of an electron is added to one mole of gaseous atoms. Shown by X (g) —> X+ (g) + e-

Question 4

Electronegativity

Answer 4

A measure of the attraction an atom has for a shared pair of electrons in a covalent bond

Question 5

Periodicity

Answer 5

Repeating trends or patterns of physical/chemical properties in elements

Question 6

Trend and explanation: Atomic Radius down a group

Answer 6

AR increases down a group as the number of electron shells increases

Question 7

Trend and explanation: Atomic Radius across a period

Answer 7

AR decreases left to right across a period because the nuclear charge increases with each added proton

Question 8

Trend and explanation: Ionic Radius for positive ions

Answer 8

IR decreases across a period because positive ions increase left to right in number of protons but decrease left to right in number of electrons; greater attractive force=smaller radius

Question 9

Trend and explanation: Ionic Radius for negative ions

Answer 9

IR decreases across a period as the number of protons increases but the number of electrons stays the same

Question 10

Trend and explanation: Ionization Energy

Answer 10

IE increases across a period and decreases down a group. Higher charge/attraction=harder to remove electrons across a period, lower attraction down a group=easier to remove.

Question 11

Trend and explanation: Electron affinity (including metals vs. nonmetals)

Answer 11

Metals=low EA, non metals=higher EA. Greater distance between nucleus and outer energy level=weaker attraction, less energy released when an electron is added

Question 12

Trend and Explanation: Electronegativity

Answer 12

Increase across a period, decrease down a group. Metals have low EN, nonmetals have high EN (gain electrons more easily)

Question 13

What is the general trend for melting point?

Answer 13

Increases across a period until group 14, then decreases (depends on bond type, structure, and strength of metallic bond)

Question 14

metallic character is…

Answer 14

how easily an atom can lose electrons

Question 15

Metalic character___down a group and ___across a period

Answer 15

Increases down a group, decreases across a period.

Question 16

Trends and explanation: atomic/ionic radius for group 1 (alkali metals)

Answer 16

Increases down a group; more energy levels.

Question 17

Trend for First IE for alkali metals

Answer 17

Decreases down a group as valence e- are further from nucleus

Question 18

Trend for electronegativity for alkali metals

Answer 18

Decreases down a group because of shielding/distance

Question 19

Trend for melting point for alkali metals

Answer 19

Decrease down a group as atoms become larger; therefore metallic bonds become weaker.

Question 20

Trend for reactivity for alkali metals

Answer 20

increases down a group as the valence electron becomes easier to lose

Question 21

What trends for halogens are the same as alkali metals?

Answer 21

AR/IR, first IE, EN.

Question 22

What two trends are different for halogens than alkali metals?

Answer 22

Melting points and reactivity

Question 23

Trend for halogens for melting point

Answer 23

increases down a group as Van Der Waal forces become greater with more electrons

Question 24

Trend for halogens for reactivity

Answer 24

Decreases down the group as attractive force between nucleus and valence e- decreases

Question 25

Properties of metals in period 3 (6)

Answer 25

Shiny, good conductors, ductile, malleable, reducing agents (form cations), metal oxides act basic and neutralize acids.

Question 26

Properties of halogens in period 3

Answer 26

Non-metals=solid, liquid, or gas. Oxidizing agents, form anions. Oxides are acidic.

Question 27

What is special about aluminum oxide?

Answer 27

It is insoluble in water and amphoteric (can be acid or base)