Unit 2: Periodic Table

Question 1

What are the three states of matter that elements can exist? Examples?

Answer 1

➡️Gas: oxygen, nitrogen
➡️liquid: Mercury
➡️solid: copper

Question 2

How did Mendeleev organize his elements? What was the underlying pattern?

Answer 2

➡️Organized his elements in columns,families/groups, and rows,periods.
➡️Rows and columns are based upon similar chemical traits and properties
↪️discovered repartition among properties and created the periodic table through the observations

Question 3

Why did Mendeleev leave gaps in his table? Did the gaps resolve?

Answer 3

➡️Gaps were left in the table because he predicted more elements were going to be found.
➡️Gaps were resolved and and Mendeleev’s predictions were correct. There are now 9⃣ basic element groups.

Question 4

How was the periodic table organized?

Answer 4

By increasing atomic mass

Question 5

Metal

Answer 5

➡️elements that can be thinned out and hammers and still retain its toughness
↪️elements that give up their electrons easily and carry electricity well
(Left side of periodic table)
➡️malleable
➡️ductile

Question 6

Nonmental

Answer 6

➡️right side of periodic table
➡️accept electrons easily but do NOT hold electricity well
↪️accept electrons to complete octet

Question 7

Transition Metals

Answer 7

➡️occupy groups 3⃣ through 1⃣2⃣ on periodic table

➡️D block or F block elements because they are known for filling the d and f orbitals

Question 8

Metalloid

Answer 8

➡️between metals (on left) and nonmetals (on right) on periodic table
↪️7⃣ total
➡️exhibit the same characteristics of metals and nonmetals

Question 9

Alkali Metals (group 1)

Answer 9

➡️ contain 1 valence electron, making them very reactive

➡️quickly combines with oxygen and water causes powerful reaction

Question 10

Alkaline Earth Metals (group 2)

Answer 10

➡️two valence electrons causing the metals to be highly reactive (lose their electrons during chemical reactions)
➡️behavior can be easily predicted
↪️form weak bases when in contacted with water; with oxygen form oxides that cause high melting points.

Question 11

Halogens (group 17)

Answer 11

➡️ 7 valence electrons; very reactive (need one more electron to make stable)
➡️ easily bonds with Alkali Metals (group 1)
➡️when reacts with metals, salt is produced
➡️only group w/ elements commonly found in each state of matter

Question 12

Noble Gases (group 18)

Answer 12

➡ unreactive because they contain a “stable set of valence electrons p)
➡️typically seen as monatomic (single atom) elements -> low boiling
➡️gas state;small % of Earth’s atmosphere

Question 13

Lanthanide Series (separate section; inner transition metals)

Answer 13

➡️atomic # fall within transition metals
➡️commonly occurs in nature, mixed “rare earth metals”
➡️difficult to separate inner metals in pure elements form

Question 14

Actinide Series (Period 7)

Answer 14

➡️unstable because most were combined in a laboratory
➡️all radioactive
➡️only three (3) metals occur naturally in this series

Question 15

Cation

Answer 15

➡️a type of ion that has more protons than electrons causing it to have a net positive charge
➡️forms when an atom loses one or more valence electrons
↪️atoms of metals

Question 16

Anion

Answer 16

➡️negatively charged ion
➡️forms when an action GAINS one or more valence electrons
↪️atoms of nonmetals

Question 17

Ion

Answer 17

➡️particle with a charge
↪️gaining or losing electrons
↪️gaining e- produces NEGATIVE from non-metals
↪️losing e- produces POSITIVE from metals and hydrogen

Question 18

Valence Electrons

Answer 18

➡️Octet Rule

↪️atoms will gain, lose or share electron I’m order to get 8 valence electrons

Question 19

Isoelectronic

Answer 19

An ion/atom etc. has the same # of electrons as what you are comparing it to.

Question 20

Ionization Energy

Answer 20

The minimum amount of energy that is required to an electron from an atom

Question 21

Atomic Radius

Answer 21

The size of an atom from the outside electron orbit to the nucleus.

Question 22

Electronegativity

Answer 22

The tendency of an atom to attack electrons and acquire a negative charge.

Question 23

Effective Nuclear Charge

Answer 23

Net positive charge that is felt by an electron in a multi-electron atom.

Question 24

Electron Shielding

Answer 24

➡️less pull with more layers

➡️answer = depends on the loss/gaining of valence electrons

Question 25

Electron Affinity

Answer 25

➡️how an atom accepts another electron

Question 26

Periods on the periodic table

Answer 26

Horizontal rows

Elements with similar properties

Question 27

Groups/families on the periodic table

Answer 27

Vertical columns
Grouped based on properties
Help to classify the elements in the periodic table

Question 28

How many elements were known in 1870?

Answer 28

Over 50 elements