Chemistry Ch. 6 Periodic Table

As you move from left to right across the periodic table electronegativity _________.

Increases

Each horizontal row on the periodic table is called what?

Period

Which group of elements has the lowest ionization energies?

Alkali metals

Which group on the periodic table is the most reactive?

Alkali metals

Which group of elements does not melt or change when placed on fire?

Alkaline-earth metals

Inner transition metals

Bottom of the table Lanthanide series and Actinide series F block elements

What do periodic table trends influence?

Energy levels and Shielding have an effect on the GROUP Nuclear charge has an effect on a PERIOD

John Newlands

- In 1863, he suggested that elements be arranged in "octaves" because he noticed (after arranging the elements in order of increasing atomic mass) that certain properties repeated every 8th element - Newlands' claim to see a repeating pattern was met with savage ridicule on its announcement. His classification of the elements, he was told, was as arbitrary as putting them in alphabetical order and his paper was rejected for publication by the Chemical Society

Johann Dobereiner

- in 1829, classified some elements into groups of three, which he called triads - the elements in a triad had similar chemical properties and orderly physical properties

Electronegativity trends

---> increases ^ increases |

Group 1A

They are the alkali metals (but NOT H)

Henry Mosley

(British physicist), arranged elements according to increasing atomic number (last person to fix periodic table)

Dmitri Mendeleev

(Russian Chemist) In 1869 he published a table of the elements organized by increasing atomic mass in first periodic table

Transition elements

Groups 3-12 Further divided into transition metals and inner transition metals Transition metals have varying electrons; they are d block elements.

Most elements on the periodic table are classified ______________.

Metals

Group 2A

They are the alkaline earth metals

For each pair, which is the LARGER size.. a. N or F b. O or O^2- c. Si or O d. Mg or Mg^2+ e. Ne or Ar f. Na or F

a. N b. O^2- c. Si d. Mg e. Ar f. Na

valence electrons

the electrons available to be lost, gained, or shared in the formation of chemical compounds

Trends

1. Group Trend - down = decreasing electronegativity (or stay the same) further down a group, the farther the e- is away from the nucleus, plus the more e- an atom has, thus, more willing to share Low electronegativity 2. Period Trend - across = increasing electronegativity Metals are at the left of the table, they let their e- go easily; thus, low electronegativity At the right end are the nonmetals. They want more electrons. Try to take them away from others High electronegativity.

PRACTICE PROBLEMS Match the element from Column A with the best matching description from Column B. Each Column A element may (usually does) match more than one description from Column B. Column A Column B 1. Sr a. halogen 2. Cr b. noble gas 3. I c. alkaline earth metal 4. N d. metalloid 5. Ar e. alkali metal 6. Rb f. representative element 7. Si g. transition element

1. c, f 2. g 3. a, f 4. f 5. b, f 6. e, f 7. d, f

Example: Al Write the electron configurations. How many valence electrons? What is the energy level of the valence electrons?

1s^2 2s^2 2p^6 3s^2 3p^1 or [Ne]3s^2 3p^1 3 3

What factors determine IE?

3. The greater the nuclear charge, the greater IE. 4. Greater distance from nucleus decreases IE 5. Filled & half-filled orbitals have lower energy, so achieving them is easier, lower IE. 6. Shielding effect

How many periods are there in the periodic table?

7

Electrons with an atomic number higher than _____ are not found naturally.

92

Ion Period Trends

Across the period from left to right, the nuclear charge increases - so they get smaller. Notice the energy level changes between anions and cations.

Group 1

Alkali metals (except H) -Forms a "base" (or alkali) when reacting with water (not just dissolved) -very reactive (usually exists as compounds) -easily lose valence electrons -react with halogens to form salt. (You will never find group 1 and group 2 (s block) by itself in mine or nature because they are too reactive.)

Elements in the s- blocks

Alkali metals all end in s^1 Alkaline earth metals all end in s^2 really should include He, but it fits better in a different spot, since He has the properties of the noble gases, and has a full outer level of electrons.

Group 2

Alkaline earth metals -Also form bases with water; do not dissolve well, hence "earth metals" -Also very reactive (You will never find group 1 and group 2 (s block) by itself in mine or nature because they are too reactive.)

Group

Also known as families; vertical column of the periodic table; numbered 1-18; similar physical group & chemical property Often identified by number and letter (IA, IIA,...)

Which type of ion typically has a larger atomic radius than the neutral atom?

Anion

Determine the group, period, block and element: a. [He]2s22p5 b. [Ar]4s2 c. [Kr]5s24d105p3

Answer: Group: 17 Period: 2 Block: p Element: F Answer: Group: 2 Period: 4 Block: s Element: Ca Answer: Group: 15 Period: 5 Block: p Element: Sb (Antimony)

Lothar Meyer

At the same time, he published his own table of the elements organized by increasing atomic mass.

Half the distance between the nuclei of two like atoms is called what?

Atomic radius

Atomic radius (atomic size)

Atomic radius decreases ---> <---Atomic radius increases ^Atomic radius decreases | | | Atomic radius increases | \/

How are elements in the periodic table organized?

Based on physical and chemical properties

Arrange the Elmer to Be, Ca, N, and P in order of increasing ionization energy.

Ca, Be, P, N

Which of the following would have the smallest atomic radius? Se^2- Sc K^+ Ca^2+

Ca^2+

F-Block

Called the "inner transition elements" f^1 f^2 f^3 f^4 f^5 f^6 f^7 f^8 f^9 f^10 f^11 f^12 f^13 f^14

Which of the following atoms would have the highest ionization energy? Francium Tin Zinc Chlorine

Chlorine

Which of the following halogens has the greatest affinity for electrons? Astatine Bromine Chlorine Iodine

Chlorine

Nonmetals tend to GAIN one or more e-

Chlorine will gain one electron P (17) no longer = the e- (18), so a charge of -1 Cl- is re-named a "chloride ion" Negative ions are called "anions" a. Anions are bigger than the atom they came from have the same energy level, but a greater area the nuclear charge needs to cove b. Anions of representative elements have the noble gas configuration after them

Which of the following atoms has the highest ionization energy? a. P b. Mg c. Na d. Cl

Cl

s-Block elements

Consists of groups 1 & 2 and He a. Group 1 = partially filled s orbital w/1 valence e- b. Group 2 = filled s orbital (2 val. E-) Because the s orbital can only hold two e-, it spans two groups! s- & p-block elements = representative elements

Which pair of elements would have similar properties due to the position in the periodic table? Calcium (Ca), Helium (He) Lithium (Li), Beryllium (Be) Copper (Cu), Gold (Au) Aluminum (Al), Zinc (Zn)

Copper (Cu), Gold (Au)

Who is the father of the modern periodic table?

Dmitri Mendeleev

Atomic and ionic sizes increase

Down and to the left

Period numbers

Each row (or period) is the energy level for s and p orbitals

Ion Group Trends

Each step down a group is adding an energy level Ions therefore get bigger as you go down, because of the additional energy level.

Which subatomic particle plays the greatest role in determining an atom's chemical properties?

Electron

Trends

Electron affinity and ionization energy Increases right and up Atomic radius Increases down and left Nonmetallic character to the right Metallic character to the left

Electrons are divided between core and valence electrons B 1s2 2s2 2p1 Br [Ar] 3d10 4s2 4p5

Electrons are divided between core and valence electrons B 1s2 2s2 2p1 Core = [He] , valence = 2s2 2p1 Br [Ar] 3d10 4s2 4p5 Core = [Ar] 3d10 , valence = 4s2 4p5

Which element has the smallest atomic radius? Fluorine Francium Lithium Radon

Fluorine

2nd Ionization Energy

For elements that reach a filled or half-filled orbital by removing 2 electrons, 2nd IE is lower than expected. True for s2 Alkaline earth metals form 2+ ions.

Driving forces

Full Energy Levels require lots of energy to remove their electrons. Noble Gases have full orbitals. Atoms behave in ways to try and achieve a noble gas configuration.

Nonmetals

Generally brittle and dull (non-lustrous), poor conductors of heat and electricity -Some metals are gases (O,N,Cl); some are brittle solids (S); only one liquid (dark red)-Br

Representative elements

Group 1,2 & 13-18, possessing a wide range of chemical, & physical properties Representative elements are the elements that exists on the earth. S and p block elements

The P-Block

Group 13 p^1 p^2 p^3 p^4 p^5 p^6

Transition metals d-block

Group 3 d^1 d^2 d^3 s^1 d^5 d^5 d^6 d^7 d^8 s^1 d^10 d^10

Transition metals

Group 3-12 D and p block elements

Group Valence e-

Group Valence e- 1 1 2 2 13 3 14 4 15 5 16 6 17 7 18 8

Atomic size

Group trends a. Increases-down As we increase the atomic number (or go down a group). . . each atom has another energy level, so the atoms get bigger. Atoms are like onions. Energy builds and builds and builds. The larger energy is on the outer edge. Larger energy group has larger radius. b. decreases - left to right Going from left to right across a period, the size gets smaller. e- are in the same energy level, but, there is more nuclear charge. Outermost electrons are pulled closer.

Hydrogen is where on the periodic table?

H is placed separately from other elements in the table; has many unique properties

This group is named __________ because they have a tendency to form salts with group 1 elements.

Halogens

Group 17

Halogens: high reactive Means "salt-forming" s^2 p^5 configuration

The closer you are from the nucleus the...

Harder it is to get the electron off. the farther it is the easier it is

Ionization (Magnesium)

If it closer to the nucleus. (For example: s orbital electrons) the attraction is greater, thus is harder to remove the electron if wanted to

ALL Periodic Table Trends

Influenced by three factors: 1. Energy Level Higher energy levels are further away from the nucleus. 2. Charge on nucleus (# protons) More charge pulls electrons in closer. (+ and - attract each other) 3. Shielding effect Inner e-s tend to shield the outer e-s from the attractive force of the nucleus The more energy levels between the valence e-s and the nucleus....more shielding

Ionization Energy (IE)

Ionization Energy (IE) - the amount of energy required to remove one e- from a neutral atom (p. 153) Removing one e- makes a 1+ ion. To avoid the influence of nearby atoms, measurements of ionization energies are made on isolated atoms in the gas phase. 1. Units: kJ/mol 2. The energy required to remove only the first e- called the first ionization energy. Think of ionization energy as an indication of how strongly an atom's nucleus holds onto its valence e- 2. The second ionization energy - the energy required to remove the 2nd e- Always greater than first IE. The third IE is the energy required to remove a third electron. Greater than 1st or 2nd IE.

The energy required to remove an electron from a gaseous atom is called what?

Ionization energy

Which of the following properties generally increases as we go from the lower left to the upper right of the periodic table?

Ionization energy

How does atomic size change as you move down a group on the periodic table?

It increases

Law of Octaves

Law of octaves, in chemistry, the generalization made by the English chemist J.A.R. Newlands in 1865 that, if the chemical elements are arranged according to increasing atomic weight, those with similar physical and chemical properties occur after each interval of seven elements.

Both Mendeleev and Meyer arranged the elements in order of increasing atomic mass. Both left vacant spaces where unknown elements should fit. So why is Mendeleev called the "father of the modern periodic table" and not Meyer, or both?

Mendeleev... stated that if the atomic weight of an element caused it to be placed in the wrong group, then the weight must be wrong. (He corrected the atomic masses of Be, In, & U) was so confident in his table that he used it to predict the physical properties of three elements that were yet unknown.

Metals

Metals are electrical conductors, have luster, malleable, ductile (able to form thin wires). These are generally solid at room temperature, shiny when smoooth and clean

Which of the following atoms has the largest atomic radius? a. C b. Na c. Mg d. P

Na

Metals tend to LOSE e- from their outer energy level

Na loses one: are now more P (11) than e- (10), thus a positively charged particle is formed = "cation" Charge is written as a # followed by a plus sign: Na1+ Now named a "sodium ion"

Which of the following atoms has the lowest electronegativity? Oxygen Lithium Neon

Neon

Which group of elements ends on the periodic table are all gases at room temperature?

Noble gases

Which group of elements is un-reactive?

Noble gases

Group 18

Noble gases: non-reactive Inert is when they do not react with other elements

Periods

Periods are the horizontal rows of the periodic table. There are 7 periods in the periodic table.

Which accurately describes nonmetals? Poor conductors of electricity Often used in computer parts Both malleable and ductile Always solid at room temperature

Poor conductors of electricity

Which of the following atoms would be most likely to lose an electron? Rb F At Li

Rb

Electron affinity

Recall: Ionization energies measure the tendency of a neutral atom to resist the loss of electrons. Example: It takes A LOT of energy to remove an e- from a neutral fluorine atom to form a positively charged ion. F(g) F+ (g) + e- ΔHo = 1681.0 kJ/mol 1. The electron affinity of an element is the energy given off when a neutral atom (in the gas phase) gains an extra e- to form a negatively charged ion. A fluorine atom in the gas phase, for example, gives off energy when it gains an electron to form a fluoride ion. F(g) + e- -> F- (g) + Energy ΔH^o = -328.0 kJ/mol

Arrange the elements S, Ge, P, and Si in order of increasing atomic size.

S, P, Si, Ge

Ionic radius

Some compounds are composed of particles called "ions" 1. An ion is an atom (or group of atoms) that has a "+" (positive) or "-" (negative) charge Recall: Atoms are neutral because the number of p = e- a. + and - ions are formed when e- are transferred (lost or gained) between atoms b. cation = positively charged ion; + (cations are pawsitive) c. anion = negatively charged ion; -

Shielding

The electron on the outermost energy level has to look through all the other energy levels to see the nucleus. Second electron has same shielding, if it is in the same period

The elements outside the periodic table is...

The inner transition elements

Squares in the periodic table

The periodic table displays the symbols and names of the elements, along with information about the structure of their atoms: Atomic number and atomic mass Black symbol = solid; red = gas; blue = liquid; outlined/white = manmade elements (from the Periodic Table on our classroom wall)

Elements can be sorted into 4 different groupings based on their electron configurations:

The s-, p-, d-, and f-block elements Note- period = n (or energy levels)

How does the atomic radius of non-metallic neutral atoms compare with their ions?

They are larger

Group 7A

They are the halogens

Group 8A

They are the noble gases

The group B are called the...

Transition elements

Which group includes some of the most familiar elements like nickel, iron, and copper?

Transition metals

Atoms with small radii tends to have high ionization energies.

True

3rd IE

Using the same logic s2p1 atoms have an low 3rd IE. Atoms in the aluminum family form 3+ ions. 2nd IE and 3rd IE are always higher than 1st IE!!!

Groups on the periodic table are arranged...

Vertically

Which properties most accurately describe the elements silicon (Si)?

Weak conductor of electricity, solid at room temperature

How many valence electrons are in an atom of each of the following elements? a. Mg d. As b. Se e. I c. Sn

a. 2 d. 5 b. 6 e. 7 c. 4

In what energy state are the valence e- of the elements listed above?

a. 3 d. 4 b. 4 e. 5 c. 5

Which orbital is filled following these orbitals? a. 4s b. 4d

a. 3d b. 5p

Trends

a. As you go down a group, the first IE decreases because... The e- is further away from the attraction of the nucleus & There is more shielding b. period trends: IE generally increases from left to right All the atoms in the same period have the same energy level Same shielding, but, increasing nuclear charge So IE generally increases from left to right. Exceptions at full and 1/2 full orbitals

Which one of each of the following Paris would you expect to have the higher electron affinity? a. Cl or Cl^- b. Na or K c. I or Br

a. Cl; Cl^- has complete shell and zero electron affinity b. Na; increases up a group c. Br

Use the following key to answer these questions (more than one answer may be correct): AEM = alkaline earth metals NG = noble gases H = hydrogen HALO = halogens AM = alkali metals a. Have full valence orbitals b. React quickly with water c. Forms 1+ ions d. Highest ionization energies e. Lowest ionization energies f. Gain 1 electron when forming ions g. Family only has one member h. Members include (s), (l), and (g) i. Forms 2+ ions

a. Have full valence orbitals NG b. React quickly with water AM c. Forms 1+ ions AM d. Highest ionization energies NG e. Lowest ionization energies AM f. Gain 1 electron when forming ions HALO g. Family only has one member H h. Members include (s), (l), and (g) HALO i. Forms 2+ ions AEM

Period and Group trends

a. Period Trend - tends to become more negative from left to right Increase in nuclear charge, decrease in size b. Group trend - decreases down a group Number of shells increase, effective nuclear charge decreases

Use the following key to answer these questions: M = metals NM = non metals S = semimetals a. Shiny and ductile b. Poor conductors c. Mg is an example d. Brittle e. As is an example f. Ar is an example g. Also called semiconductors h. Si is an example i. Good conductors j. H is an example

a. Shiny and ductile M b. Poor conductors NM c. Mg is an example M d. Brittle NM e. As is an example S f. Ar is an example NM g. Also called semiconductors S h. Si is an example S i. Good conductors M j. H is an example NM

Identify each of the following elements: a. an electron configuration of [Kr]5s24d105p2 b. 5 valence e-, 6th energy level c. 2 valence e-, 1st energy level d. 3 fewer e- in the 4th energy level than Kr e. an electron configuration ending in 4p2

a. Sn (Tin) b. Bi (Bismuth) c. He d. As e. Ge (Germanium)

What are the general trends in electronegativity? a. across a period? b. down a group?

a. increase b. decrease

Trends

a. move left to right across a period the size of + ion decreases, then - ions decreases (look at when ion + or - "starts") b. down a group, ions get larger (adding energy level

Which elements fit the following descriptions? a. the smallest alkaline earth metal b. has the highest electronegativity value c. the halogen with the lowest ionization energy d. has 13 more electrons than argon e. is found in period 3, group 13 f. the Group 14 element with the largest ionization energy g. its 2+ ion has the electron configuration [Kr]

a. the smallest alkaline earth metal Be b. has the highest electronegativity value F c. the halogen with the lowest ionization energy At d. has 13 more electrons than argon Ga e. is found in period 3, group 13 Al f. the Group 14 element with the largest ionization energy C g. its 2+ ion has the electron configuration [Kr] Sr

F and d orbitals are...

are farther away from the nucleus and have more energy

Metalloids

border the stair step line-2 sides Properties are intermediate between metals & nonmetals Sometimes referred to semimetals

p-block elements

consists of groups 13-18; has partially filled or filled p orbitals Why no p-block elements in period 1? p doesn't exists until period 2 or energy level 2 (n=2)! a. s- & p-block elements = representative elements

f-Block elements

contains the inner transition metals filled or partially filled outermost s orbital and filled or partially filled 4f & 5f orbitals a. e- do not fill f in predictable pattern b. f holds 14 e-s (7-f orbitals), so 14 columns

d-Block elements

contains the transition metals; largest block a. usually filled outermost s orbital & filled or partially d orbitals (are exceptions!) b. d starts @ period 4

The energy change involves in gaining an electron...

electron affinity

The "d" orbitals...

fill up in levels 1 less than the period number, so the first d is 3d even though it's in row 4

Atomic radius

is half the distance between the two nuclei of a diatomic molecule

Electronegativity

is the tendency for an atom to attract e- to itself when it is chemically combined with another element They share the e-, but how equally do they share it? An element with a big electronegativity means it pulls the electron towards itself strongly!

Metal atoms tend to __________ electrons and form _______ ions.

lose; positive

Which block in the periodic table contains the halogens?

p

The ___________ ___________ is the most important tool in the chemist's toolbox.

periodic table

Chemists used the ___________ of elements to sort them into groups.

properties

Elements in ten 1A-8A groups are called the..

representative elements Outer s or p filling

Cations are _________ than the atom they came from (+ more info)

smaller; not only do they lose electrons, they lose an entire energy level Cations of representative elements have the noble gas configuration before them

The "f" orbitals...

start filling at 4f, and are 2 less than the period number

Periodic Law

states that when the elements are arranged by increasing atomic number, there is a periodic repetition of their properties (repetition of chemical & physical properties)

What determines the blocks?

the energy sub-level being filled

The closer the Electron is to the nucleus...

the larger the attraction is. The farther, the less attracted it is

Measure the atomic radius

this is half the distance between the two nuclei of a diatomic molecule.

Linus Carl Pauling (1901 - 1994)

was an American chemist and peace activist. He is considered one of the most influential chemists in history and ranks among the most important scientists of the 20th century. Pauling is one of only two individuals awarded two Nobel Prizes in different fields (Chemistry and Peace prizes), and the only person awarded two unshared prizes.

Noble gases element ....

will not get rid of electrons unless you use a lot of energy