Periodic Trends

Question 1

periods

Answer 1

are rows on periodic table

Question 2

groups

Answer 2

are columns on periodic table

Question 3

alkali metals location and properties?

Answer 3

Group 1. low ionization energies, react explosively with water (Exothermic, always forms H2 gas), form ionic compounds

Question 4

alkaline earth metals location and properties?

Answer 4

Group 2. low ionization energies, don’t react as violently with water, get more reactive with water as you go down the group

Question 5

halogens location and properties?

Answer 5

Group 17 (with F, Clm BR, etc).highly electronegative, high electron affinities, highly reactive with metals, good oxidizing agents (they want to be reduced aka Gain Electron -GER)

Question 6

noble gases

Answer 6

Group 18. inert (unreactive) gases

Question 7

Transition metals located where? Form _____ compounds?

Answer 7

D block elements. form colorful compounds due to the way their d-orbitals behave

Question 8

oxygen group, makes a good _____ agent?

Answer 8

O2 is a good oxidizing agent, but O3 is even better oxidizing agent. Likes to react with metals to form metaloxides

Question 9

Metals make up _____ of the periodictable? Except where?

Answer 9

most of the periodic table, except top right corner and H

Question 10

nonmetals are found where on periodic table?

Answer 10

top right corner + H

Question 11

Metalloids are located where on periodic table?

Answer 11

create a diagonal line from B down to At in bottom right corner

Question 12

atomic radius

Answer 12

the distance from a nucleus of an atom to the outside of its outermost orbital

Question 13

bond length

Answer 13

the distance between two bonded atom’s nuclei

Question 14

Why do atoms get larger as you go down a group?

Answer 14

higher energy shells “n” shell = larger size

Question 15

Why do atoms get smaller as you move across a period, from left to right?

Answer 15

greater effective nuclear charge = smaller size. In other words, the more electronegative an atom (the more an element wants an e-), the smaller the atom. There are more protons to attract e- as you move left to right BUT you’re still in the same shell, so the protons hold everything closer/tighter together (smaller).

Question 16

Do ion sizes increase or decrease with more e-?

Answer 16

more e- (anions) = larger size

less e- (cations) = smaller size

Question 17

What is an isoelectronic series?

Answer 17

group of different elements that have the same number of e-

Ex: O-2, F-, Ne, Na+, Mg+2

Question 18

In an isoelectronic series, how do you determine size?

Answer 18

By the number of protons. More protons means there is more strength to such e- in tighter making it SMALLER
ex: F-is smaller than Na+

Question 19

ionization energy definition

Answer 19

energy required to remove an electron from an atom

Question 20

what is the ionization energy trend on the period table?

Answer 20

increases as you go UP and to the RIGHT on periodic table (He has highest IE). We DO include noble gases

Question 21

Where would it be the hardest or require the most energy to remove an e- at in accordance to ionization energy?

Answer 21

• Top right (He) requires the most energy to remove an e-

* bottom left requires the least amount of energy to remove on e- (Fr)

Question 22

What is the size trend on periodic table?

Answer 22

get larger as you move down and to the left

Question 23

Ionization energy AND electron affinity exceptions

Answer 23

1) Be is greater than B, full 2s2 so relatively stable
2) N greater than O, full 2p3 so it takes more energy to strip these e- bc it’s relatively stable
* Electron affinity is both 0 for Be and N

Question 24

Is an atoms first ionizationenergy smaller or larger than its second? or its second compared to third?

Answer 24

smaller. (OR every successive ionization energy is larger than the previous one)

Question 25

What does first Ionization energy, second IE or 3rd IE mean?

Answer 25

1st IE = first e- striped away
2nd IE = second e- removed
3rd IE = third e- removed
–takes more energy for every new e- removed

Question 26

when would you have the LARGEST ionization energy for an atom?

Answer 26

When the atom feels like a noble gas, it’ll have HUGE IE bc it’s met the octet rule and doesn’t want to lose any e-

Question 27

Electronegativity definition

Answer 27

how “thirsty” an atom is to gain e-

Question 28

trend of electronegativity

Answer 28

increases as you move to the right and up, excluding the noble gases (F is the most electronegative)

Question 29

electron affinity definition

Answer 29

the energy given off/produced when an atom gains an electron (basically the opposite of ionization energy)

Question 30

is electron affinity endothermic or exothermic?

Answer 30

exothermic

Question 31

What is the trend of electron affinity?

Answer 31

increases as you go UP and to the RIGHT. This trend is the same as electronegativity because it excludes noble gases. (chlorine (Cl) has the highest electron affinity, not F)

Question 32

Why does Cl have a higher electron affinity than F?

Answer 32

Don’t need to know why. It just does. But F has greater electronegativity.