Periodic Table Trends Chapter 4

Question 1

What is a periodic trend?

Answer 1

Properties that show patterns when examined across the periods or vertically down groups.

Question 2

What happens when an atom forms an ion?

Answer 2

Rhe stability of an octet of e- enables you to predict the number of electrons to gain or loss. You can then predict the change on the ion formed.

Question 3

What is the trend of the atomic radius?

Answer 3

Further down on periodic table = larger atomic radius

Question 4

What is the trend of ionization energy?

Answer 4

Top left has highest ionization energy, bottom right has the lowest ionization energy

Question 5

What us the trend of electronegativity

Answer 5

As you go down, electronegativity decreases. As you go left to right, electronegativity increases (remember that the effect from left to right is much greater than the effect going down) (hydrogen needs to go between boron and carbon)

Question 6

What is electronegativty related to?

Answer 6

Electronegativity is related to ionization energy

Question 7

What are the characteristics of metals?

Answer 7

Shiny, Solids, stretched and shaped, conductors of heat and electricity

Question 8

What are the characteristics of nonmetals?

Answer 8

Solids, liquids, or gases

• Most are not solid at room temperature
• If they are a solid, they are dull and brittle
• Poor conductors of heat and electricity

Question 9

What are semiconductors/ metalloids?

Answer 9

Contain properties of both metals and nonmetals

-Ex-Conduct electricity well but are also a liquid

Question 10

What is the element that does not follow the trend of being a metalloid?

Answer 10

Aluminum; Because it is a metal instead

Question 11

The majority of the periodic tables on the left are _______?

Answer 11

Metals

Question 12

How do you tell if something is a metal?

Answer 12

One the lefthand side of the zigzag line (except for hydrogen)

Question 13

How do you tell if something is a nonmetal?

Answer 13

If its on the right hand side of the zigzag (includes hydrogen)

Question 14

How do you tell if something is a metalloid on the periodic table?

Answer 14

Touching zigzag line (other than aluminum)

Question 15

What are the different kinds of metals?

Answer 15

Alkali metals, Alkali-earth metals, and transition metals

Question 16

What are alkali metals?

Answer 16

Soft, shiny, and very reactive (column on the leftmost periodic table)

Question 17

What are alkaline-earth metals?

Answer 17

Less reactive (Found in seconf column of the periodic table)

Question 18

What are transition metals?

Answer 18

Have different uses,and are found in center of periodic table (from Sc to Zn columns)

Question 19

What are noble gases?

Answer 19

Mostly non-reactive gases, very stable (elements on rightmost column of periodic table)

Question 20

What are halogens?

Answer 20

Very active, gain one electron to form a stable compound (found on 2nd to last column of periodic table)

Question 21

What are diatomic gases

Answer 21

Chemical elements that form stable homonuclear diatomic molecules (these 7 are H2
 N2
 F2
 O2
 I2
 Cl2
 Br2

Question 22

What is ionization energy?

Answer 22

How tightly a valence is held to the electron cloud.

Question 23

How does the periodic table help you figure out how many valence electrons there are?

Answer 23

Elements in the same group of the periodic
table (column) have the same number of valence
electrons. There is a pattern that can be
observed.

Question 24

Define Shielding Effect:

Answer 24

Inner electrons shield the valence
electrons from the attractive force of the nucleus.
The nucleus has less pull with more shielding.

Question 25

Shielding is related to the _________________ from teh Bohr Model

Answer 25

Number of rings

Question 26

The further down you go on the periodic table, the ________ the shielding

Answer 26

Greater

Question 27

What is the effective nuclear charge trend?

Answer 27

As you add more protons, to an atom in the same energy level (ring), you increase the pull of the nucleus on electrons.

Question 28

REMEMBER: Shielding is increased with # of rings as you go down, and then increases as you go left. -Effective nuclear charge is greater when you go down or right, because it is increasing protons.

Answer 28

REMEMBER: Shielding is increased with # of rings as you go down, and then increases as you go left. -Effective nuclear charge is greater when you go down or right, because it is increasing protons.

Question 29

Atoms of elements in the same group have the __________ electrons and therefore behave similarly

Answer 29

same # of valence

Question 30

•All elements in a period have their valence electrons in the same __________

Answer 30

Energy Level

Question 31

Electron Dot Diagrams show the ____________ of an | element.

Answer 31

valence electrons

Question 32

What is the atomic radius?

Answer 32

•The atomic radius of an element is one half of the distance between the nuclei of two atoms of the same element when the atoms are joined. (measured in picometers)

Question 33

What is the trend of atomic radius?

Answer 33

``` Atomic radius increase as you move down because each atom has another energy level (more shielding), so the atoms get bigger. ```

Question 34

What are the periodic trends?

Answer 34

As you go across a period, the radius gets smaller. • Electrons are in same energy level (same shielding).

Question 35

Another word for the atomic radius is ____________

Answer 35

Size of the atom

Question 36

REMEMBER: Atomic radius gets smaller left to right, but bigger as you go down

Answer 36

REMEMBER: Atomic radius gets smaller left to right, but bigger as you go down

Question 37

When is an ion formed?

Answer 37

An ion is formed when the number of electrons changes compared to the neutral atom.

Question 38

How do atoms become ions?

Answer 38

Atoms become ions based on the octet rule or | duet rule to become like their closest noble gas (rightmost column)

Question 39

What is the rule for changing an atom into an ion?

Answer 39

Just ask yourself is it easier to lose or gain a given number of electrons to be like its nearest noble gas (group 8A).

Question 40

What is the oxidation state/charge of Li? (REMEMBER oxidation state is related to changing atoms into ions)

Answer 40

1+; Because it has to lost 1 electron to become equal to become equal to 8A, so its 1+

Question 41

What are cations?

Answer 41

``` Cations are positively charged ions • Cations form by losing electrons. • Cations are smaller than the atom they come from. • Metals form cations. ```

Question 42

If the oxidation number is a positive charge, then it is an ____

Answer 42

Cation

Question 43

What are anions?

Answer 43

``` Anions are negatively charged ions • Anions form by gaining electrons. • Anions are bigger than the atom they come from. •Nonmetals form anions. ```

Question 44

If the oxidation number is a negative charge, then it is an ____

Answer 44

anion

Question 45

What does isoelectric mean?

Answer 45

Isoelectric means it has the same number of electrons.

Question 46

How do you order elements for isoelectric sequence?

Answer 46

Put K+, P3-, Cl-, Ar, S2-, and Ca2+ in order of decreasing size. * 1st find the number of electrons each atom/ion has * Notice they all have 10 electrons now. * 2nd Find the number of protons for each atom/ion. * K+ has 19 p+, P3- has 15 P+, Cl- has 17 p+, Ar has 18 protons, S2- has 16p+, Ca2+ has 20 p+ * 3rd Put them in order of increasing number of protons. * This will be the size from largest to smallest. * P+,S2-,Cl-,Ar,K+,Ca2+

Question 47

What does ionizatio eneergy state?

Answer 47

Electrons are held in atoms by their attraction to the positively charged nucleus.  To remove an electron requires energy. ```  Ionization energy is the energy required to remove the least tightly bound (or outermost) electron from an atom. ```

Question 48

What is the trend of ionization energy?

Answer 48

Decreases from top to bottom | -INcreases from left to right

Question 49

What is electronegativity?

Answer 49

Electronegativity is the tendency of an element to attract electrons in a bond.  Therefore, elements that want to gain electrons will have higher electronegativity.

Question 50

What is the trend for electroegativity?

Answer 50

Same for ionization energy Decreases from top to bottom -INcreases from left to right