Chem FINAL

decomposition

AB → A + B

Single Displacement

Element + Compound → Compound + Element

(A + BC → AC + B)

\
(Zn + H2SO4 → ZnSO4 + H2)

Ionic bonds

transfer of electrons

Covalent bonds

sharing of electrons

Anion

negative ions

* more negative because they **gain** electrons
* nonmetals
* end in -ide

Cation

Positive ions

* more positive because the **lose** electrons
* metals

Octet Rule definition

atoms tend to gain, lose, or share electrons in order to acquire eight valence electrons (noble gas configurations)

Non-metals tend to

gain electrons

Metals tend to

lose electrons

When two elements transfer electrons

Ionic bond is formed

Diatomic Molecules

N2, H2, O2, Cl2, F2, Br2, I2,

* forms a seven on the periodic table
* atoms are chemically bonded
* exist in nature
* two of the same types of atoms

Alkali metals & Alkaline Earth Metals bond with

Halogens

Oxides

A metal forms a bond with oxygen

Binary Compounds

two elements

Monatomic

containing one atom

Polyatomic ions

Composed of *more than* two elements

Salt is formed

A non-metal and a metal

Properties of Ionic compounds

* hard but brittle
* high boiling and melting points
* __Solids__ **dont** conduct electricity
* __Liquids/Solutions__ conduct electricity

Diatomic molecules bond

Diatomic covalent bonding

Water

polar covalent compound

* oxygen has six valence electrons
* each hydrogen atom has one valence electron

Types of Covalent Bonds

Single Bonds, Double Bonds, Triple Bonds

SIngle Bond

atoms share **one pair** of electrons **(2)**

Double Bonds

atoms share **two pairs** of electrons **(4)**

Triple Bonds

atoms share **three pairs** of electrons **(6)**

Lewis structures show

arrangements of electrons and bond

Strenght of a covalent bond is dependent on

bond length

Bond Length

the distance between two bonded nuclei

Bond-Dissociation energy

amount of energy needed to break bonds

* Inverse relationship between bond length and bond energy

Conversion for temperature (SI Unit)

273° K = 0° C

Lewis structures can predict

molecular shape

Unshared pairs of electrons can influence

molecular shape

Molecular orbital

the region of high probability that is occupied by an individual electron as it travels with the wavelike motion in the three-dimensional space around one of two or more associated nuclei

Dipole

has a slight negative and positive end

The symbol *𝛿*

shows partial negative or partial positive charge

Electronegativity

determines Bond Type

Polarity

related to Bond Strength

Reactions occur when

substances undergo changes

Bonds are ______,__ and new bonds are ____ in a chemical reaction

broken, formed

Combustion reactions always have

Water (H2O) and Carbon Dioxide (CO2) on the product side

△

heat has been added

Products

substances formed by reaction

* right of the arrow

States of matter

(s), (l), (g), or (aq)

Evidence of a Chemical Change

* color change
* evolution of a gas
* formation of a precipitate
* release or absorption of energy

Endothermic

absorption of heat

exothermic

release of heat

What is the **study of quantitative relationships** between the amount of reactants used and the amounts of products formed by a chemical reaction

Stoichiometry

Percent Yield

Percent Yield = (Actual Yield / Theoretical Yield ) x 100

Stoichiometry is based on the law of. . .?

Conservation of mass

When atoms or ions are used in an equation what conversion factor must be used?

Avogadro’s Constant

What is always the first step in a stoichiometry problem

The given

Double Displacement

Compound + Compound → Compound + Compound

(AD+ BC → AC + BD)

\
(AgNO3 + NaCl → AgCl + NaNO3)

(\*metals go with nonmetals\*)

Combustion

compound/elements + O2 → products

(CH4 + **O2** → *CO2 + H2O*)

Synthesis

A + B → AB

(Zn +I2 → ZnI2)

1

mono

6

hexa

0\.5 - 2.1

polar covalent

Linear

Trigonal Pyramidal

Which atom is most likely to form a triple covalent bond

Carbon

Bent

Tetrahedral

2

di

3

tri

4

tetra

5

penta

7

hepta

8

octa

9

nona

10

deca

Covalent bonds are between

two nonmetals

Bonds lengths ______ distances because bonds are ______

average, rigid

A gaseous substance with poor conductivity is most likely a(n) ________________.

A non-metal/molecular compound

Pt symbol

a catalyst

Ag(s) + NaCl(aq) →

Na(s) + AgCl(aq)

SI unit for amount

Mole/Mol

A mole is

the number of atoms in exactly 12 grams of carbon-12

number of particle in a mole is called

Avogadro’s Number

(6.022 x 10^23)

Mole ratio

the key in Stoichiometry

Mole ratio is

a ratio between the number of moles of any two substance in a balanced chemical equation

limiting reactant

determines the amount of product formed

* determines the theoretical yield
* the one that runs out first

excess reactant

the reactant that is left over

Theoretical Yield

the maximum amount of product that can be formed from a given reactant

* Theoretical Yield is higher than actual yield

Actual Yield

the amount of product produced in a chemical experiment

Percent Yield

the ratio of actual yield to theoretical yield

* describes the efficiency of a reaction

Precent Yield formula

Percent yield = actual/theoretical x 100

Coefficients in a chemical equations are used in which one of the following conversion factors?

mole ratios

In stoichiometric calculations, you should:

round off only the final answer

Boyle’s law

inverse relationship between volume and pressure

* “volume of a fixed amount of gas at constant temperature varies inversely with pressure”
* P1V1 = P2V2

As volume increases

pressure decreases

As volume decreamses

pressure increases

Charles’ Law

Direct relationship between volume and temperature

* “the volume of a given amount of gas is directly proportional to the Kelvin temperature
* V1/T1 = V2/T2

As temperature increases

volume increases

As temperature decreases,

volume decreases

0° Celsius

273° Kelvin

* uses for all v/t equations
* used in p/t problems

Gay-Lussac’s law

Direct relationship between pressure and temperature

* “The pressure of a fixed amount of gas varies directly with Kelvin temperature when volume remains constant”
* P1/T1 = P2/T2 **OR** P/T = K

As temperature increases

pressure increases

As temperature decreases

pressure decreases

Which is **not** a unit which describes pressure?

Newton

Finding the Percent of an Element in a Compound Formula

element/compound x 100

Triagonal Planar