Chemistry: Units 3-4

Periods

The rows across the periodic table

There are ____ periods.

7

Periods have the increase in ______ heading right.

protons

Groups

The columns up and down the periodic table

There are ______ groups.

18

Groups have all the same what?

Amount of valence electrons

Metals have a ____ charge.

+

Non-metals have a _____ charge.

-

10 Periodic Families

1. Alkali metals

2. Alkali earth

3. Transition

4. Post-transition

5. Halogens

6. Noble gases

7. Metalloids

8. Lanthanides

9. Actinides

10. Reactive non-metals

It takes ______ of years for a star to expand before _______.

millions, exploding

Different colors of stars means what?

The star changes its size and resources it has (they implode when they stop burning)

Mostly metals on periodic table = mostly ________ = most of _______.

solids, table

The phases of elements are based upon “_____ _______.”

room temperature

Room temperature

25 C, 77 F

The formation of Earth was due to ______.

stars

Stars

Balls of hydrogen that under pressure and high temperature they collide with each other forming helium and elements up to iron

Nuclear Fusion

When stars collide with each other and form helium and elements up to iron when under pressure and high temperature

Supernovae

A giant explosion of the stars when they die and what elements past iron were formed through

Alkali metals

• They have 1 valence electron = highly reactive (explosive)

Alkali earth

• These are the 2nd most reactive metals because they have 2 valence electrons (aren't as explosive, but still highly reactive)

Reactive Non-Metals

• Make negative charges and have very low melting points except for carbon

Transition metals

• Mostly used to build tools, structures, and items

Post-transition

• Charges of +3 with the others further to the right having +2 or +4 charges

• They are after and have larger melting points than transition metals

• So soft, used in high tech items (aluminum foil)

Metalloids

• These can act as nonmetals or metals (makes them unique)

• Can form both anions and cations

Lanthanides

• Shiny white metals with varying properties

Actinides

• Extremely radioactive metals

• Very short-lived and unstable

Halogens

• The most reactive nonmetals because they have 7 valence electrons

• Common react with the alkali and alkaline earth metals

Noble gases

• Doesn’t react with other elements because they have perfect octet of valence electrons (nonreactive)

Symbol

A combination of letters to tell us what element we are talking about

Subscripts

The numbers of the bottom right of the symbols that tell us how much what element makes up a compound

Coefficients

Tell us how many compounds of elements there are

2C>6H>12O>6 symbols?

C, H, O

2C>6H>12O>6 subscript?

6, 12, 6

2C>6H>12O>6 coefficient?

2

Bonding

When there is an attraction between two molecules that makes them connect or stay together

Ioic bonds

When atoms connect to each other due to differences in charge

NaCl

Since Cl-1, NaCl gets +1 from Na

Polyatomic ions

When sometimes things bond to each other but still carry a charge. These are found in Table G.

Process for naming ionic compounds for regular ionic bonds

1. Name the Cation (positive atom) as it I called on the periodic table

2. Name the anion (negative atom) as it is called on the periodic table with the end of -ide

Process for naming ionic compounds for polyatomic bonds

1. Use the the same naming conventions as regular ionic bonds, but just use the polyatomic ion’s name

Chemical equation

A mathematical way to show when things are built up or broken down in chemistry

Reactants

Things that go into the chemical equation

Products

Things that go at the end of a chemical equation

Law of conservation of mass

Matter is not created or destroyed it is just converted into different atoms

Balancing equations

The process of matter sure there’s an equal amount on both sides by adjusting coefficients

Potassium Oxide reacts with Copper (I) Chloride to yield Potassium Chloride and Copper (I) Oxide

K>2O + 2CuCl —> 2KCl + Cu>2O

Synthesis reaction

A reaction when two simple elements combine to build a compound

Decomposition reaction

A reaction when a singular compound is broken into its basic elements

Single replacement reaction

One where a compound and an element swap spots with similar ions

Double replacement reaction

Always 2 compounds combine together and swap ions from each compound

Top 5 common elements for percent abundance

1. Hydrogen

2. Helium

3. Oxygen

4. Carbon

5. Neon

Hydrogen percent abundance

74%

Helium percent abundance

24%

Oxygen percent abundance

1% (ab)

Neon percent abundance

0.13% (ab)

The drop off for percent abundance is ______.

steep

Large elements are not common because why?

They are unstable due to too many protons close together that repel each other

Nuclear Decay

When an element is too large and unstable and it breaks into smaller more stable elements (too many protons)

Atomic radius

The radius of an atom or width from center to edge

Atomic radius based on what 2 things?

1. The amount of protons and electrons

2. The effective nuclear charge

Effective nuclear charge

The amount of positive pull from the protons in the nucleus of an atom

Is Na+ able to pull electrons well?

No (+1 valence electrons and doesn’t have high effective nuclear charge)

Ionization energy

The energy required to remove an electron

What does ionization energy depend on?

1. How close the atom is to the octet

2. How high the effective nuclear charge is

Electronegativity

The tendency for an atom to hold onto electrons more strongly than other atoms 

Protons and electrons work like ______ that hold onto each other.

magnets

Higher _____ _____ ______ means more pull.

effective nuclear charge

Effective nuclear charge =

number of valence electrons

Na +1 is how strong the _____ is (valence _______).

pull, electrons

For atoms, it’s ______ energy to keep electrons, and less energy to give them _______.

more, away

Atoms want to be at _____ so if they are close to ____, they are willing to part with their electrons and become positive.

8,0

Other atoms may be close to _____ and not want to give up their _____, so it takes more _____ to steal them.

8, electrons, energy

High ionization energy = high _______.

electronegativty

K has 1 valence electrons and has an effective nuclear charge of ______.

+1

Electronegativity has the same trend as ionization energy why?

Because if an atom is more electronegative, it grabs electrons more and doesn’t want to lose them (ionization)

What’s the rule with radii?

The more up and right, the smaller the radius, and the more left and down, the smaller the radius (decreases as you go up and right)

Gamma decay

Same but add energy symbol

Alpha decay

-4/2 (He)

Beta decay

0/+1

Metals are known for their

• Conductivity

• Malleability

• Ductility (plastic deformation)

• Lustrous

• React with Copper (II) Chloride

Non-metals are best know fortheir 

• Non-conductivity

• Not lustrous

• Brittle

• Do not react with Copper (II) Chloride

• Metalloids are a combination of both sets of properties

Bonding

The attraction between two or more elements

Balancing

Stating how many elements or compounds are needed to complete a chemical reaction