Year End Exam Review, Day 3.pptx

Year End

Review

Alkyl Groups

•

CH

₃

: methyl

•

CH

₃

C

₂

: ethyl

•

CH

₃

CH

₂

CH

₂

: propyl

•

CH

₃

CH

₂

CH

₂

CH

₂

: butyl

•

CH

₃

CH

₂

CH

₂

CH

₂

CH

₂

: pentyl

Rules for naming organic compounds

1) Identify longest carbon chain

2) Identify the alkyl (substituent) groups

3) Number the carbons starting from the

end closest to the substituents

4) Give the substituents an address

5) If you have multiples of the same

substituent, use prefixes: di-, tri-,

tetra-Naming Alkenes and Alkynes

1) Identify longest carbon chain

2) Number carbons from end closest to double

or triple bond

3) Give the double or triple bond an address

4) Double and triple bonds take precedence

Energy: Potential, Kinetic, Chemical

Chemical Energy: A type of potential

energy stored in bonds

Potential Energy: Energy of Position

Kinetic Energy: Energy of Motion

When an energy releasing reaction takes place,

bonds break on the reactant side, and new bonds

are formed on the product side



_{This yields products with}

different and more stable

bonding arrangements



_{The products have less}

chemical energy than the

reactants…the energy

originally stored in the

reactants is released as heat

and/or light

Step 1: Old Bonds are broken

•

_{Requires energy---endothermic}

•

_{The energy is needed to pull apart the}

bonds---it is a reactant

Step 2: New Bonds are Formed

•

_{Releases energy as the new bonds are}

formed---exothermic

C + 4 H + 4 O → CO

+ 2 H

O + energy

The balance between the energy that is needed

to be put in, and the energy that is produced

when bonds are formed determines if the

When the energy released

(exo) in forming new bonds is

greater that the energy

needed (endo)to break the

old bonds, the

overall

chemical reaction is

exothermic—

Law of Conservation of Energy

Energy can be converted from one form to

another, but energy is never “used up”

Chemical → Thermal →

Specific Heat Capacity

Heat needed to raise the temperature

of one gram of the material by one

degree Celsius



_{Each material}

has a different

specific heat

capacity

•

_{Specific Heat Capacity for Water is:}

4.2 J/(g x ° C)

--3 ways this can be measured?

J = Joules

Molar Heat of Combustion

•

_{Esters: suffix -ester}

Functional Groups Containing Nitrogen

Amines---suffix “-amine”

Amino Acids (building

blocks of proteins)

Aldehydes: (suffix-al)

Alkyl Halides

•

_{One or more halogens replace a}

Polymers

Alternative Fuel Sources

•

_Biodiesel

•

_Electricity

•

_Hydrogen

•

_{Natural Gas}

•

_{Vegetable Oil}

•

_Bio-mass

Pressure

•

_{Pressure = Force/Area}

–

_{(Force is expressed in}

–

_{Newtons, Area is m}

₎

1 Newton/1 m

_{= 1 Pascal}

Kinetic Molecular Theory (KMT)

1) Gases consist of tiny

particles of negligible

volume that are far apart

in size

2) Gas molecules are in

constant, random motion –

kinetic energy—

elastic

The atmosphere (troposphere) 15 km of

the earth’s surface: 78% N; 21% O

Gases

•

_{Molar Volume of any gas : 22.4 L/mol}

•

_{To describe the properties of a gas you}

need 4 measurable quantities:

temperature, pressure, volume,

quantity



_{To convert kPa to atm: 101.2 (101.3) kPa = 1}

atm



_{To convert °C to K: add 273 to °C}



_{STP = 0 °C and 1 atm}

Gas Laws

Boyle’s Law: P

V

= P

V

Charles’ Law V

/T

= V

T

Gay-Lussacs’ Law: P

/T

= P

/T

Combined Gas Law: (P

x V

)/T

= (P

xV

)/T

Avogadro’s Law: equal volumes of gas at the same

temp and pressure contain the same number of

molecules

Ideal Gas Law: PV = nRT

R = 0.0821 L atm

Limiting Reactants

Limiting

Reactant/Reagent:

Limits or determines the

amount of product that

can be made

Excess reagent: More than

enough reactant to drive

reaction to completion

More than enough green

molecules (excess reactants), not enough red atoms for all the green molecules to pair up with (limiting reactant

•

_{To solve LR problems, you must first}

identify the limiting reactant. Often this

involves using molar relationships

•

_{Then, solve the problem using that}

limiting reactant as the reactant that

will drive the reaction to completion.

Greenhouse Gases vs.

Global Warming

•

_{Greenhouse Gas is normal, and vital for life}

on earth

•

_{Global Warming, caused by a depletion of}

Acid Rain

•

_{Any precipitation with a pH}

lower than ≈ 5.6 is acid rain.

H

0 + CO

→

H

CO

(carbonic acid)

Leads to: erosion of monuments,

deforestation of plants, fish kills

in lakes

Arrhenius Acids and Bases

Acid: Any substance that

generates or increases the

concentration of Hydrogen (H

)

ions in an aqueous solution

Base: Any substance that

produces or increases the

concentration of hydroxide (OH

)

ions in an aqueous solution.

•

Acid solutions: more H

O

than OH

-•

_{Alkaline solutions: more OH}

than

H

O

Water and other neutral substances

have equal amounts of H

O

and

OH

-Neutralization Reaction

H

O

+ OH

2 H

O

A one point change in pH represents a 10 x

change in acidity or alkalinity

Molar Concentration

Molar Concentration (Molar-

M

)

M

= mol solute

L

solution

The higher the Molarity, the higher

the concentration

Strong vs. Concentrated

Weak vs. Dilute



_{An acid is strong if it completely ionizes}

(forms ions in solution)—it will produce

hydronium ions and anions



_{A base is strong if every dissolved}

molecule produces a hydroxide ion and a

cation



_{Concentration and dilute refer to how}

Equivalence Point



_{When two}

solutions used in

titration are

present in

chemically

Titration

The controlled addition

and measurement of a

solution of known

concentration required

to react completely

with a measured

amount of a solution of

unknown concentration



_{A known solution is used to determine the}

molarity of another solution by titration

1) Start with a balanced equation and

determine the chemically equivalent

amounts of acid and base

2) Determine the moles of acid (or base) from

the known solution

3) Determine the moles of solute of the

unknown solution used during the titration

4) Determine the molarity of the unknown

Buffer Solutions: mop up excess hydronium

or hydroxide ions

Buffer solutions is a solution of a weak acid and its conjugate base or a weak base and its conjugate acid

The pH remains relatively constant when small amounts of strong acid or strong base are added.

They have highly stable pHs (will not vary by more than 1 pH unit)

A buffer is a solution of a weak acid and one of its salts (or a weak base and one of its salts)

Le Chatelier’s Principle

•

_{When a system at equilibrium is}

disturbed by application of a stress, it

attains a new equilibrium position that

minimizes the stress

Biochemistry:

Four Main Classes of Molecules

•

_{Carbohydrates}

•

_Proteins

•

_Lipids

•

_{Nucleic Acids}

Macromolecules: Polymers (made of monomers)

A cell makes thousands of different

Making polymers:

dehydration

reaction

Breaking polymers:

hydrolysis

Three main polysaccharides:

Starch: Found in plants—banks from which plants can draw

glucose for energy or building materials

Cellulose: most abundant organic material on earth--make tough walls of plant cell walls

Glycogen: stored in liver and muscle cells-- hydrolyzed when glucose is needed by the body

Carbohydrates, monosaccharides (simple sugars) and

polysaccharides: macromolecules—polymers made of hundreds to thousands of monosaccharides linked together by

Proteins—Main use is as enzymes

Amino acids are compounds

with an amine functional

group and a carboxylic group

Proteins are polymers of 20 different

amino acid monomers in chains of

100 – 1000’s bonded together covalently

with “peptide” bonds. A chain of AAs is

called a polypeptide chain. Function is

determined by the arrangement and

shape of these 20 AAs.

Lipids

Energy storing hydrocarbons linked by non-polar

covalent bonds



_Hydrophobic



_{High energy!}

_{9.8 kcal/gram}

vs. 4.1 kcal/g of sugars and

proteins

Three kinds of lipids:

 _{fats and oils (also waxes) –long term energy storage}

 _{phospholipids—main component of cell membranes}

Cell Membranes:

Phospholipid Bi-Layer

Hydrophilic “heads” and

hydrophobic “tails” regulate

what goes into and comes

out of cells

Nucleic Acids

• _{Macromolecules necessary for storing and directing the}

information that human cells use for reproduction and growth

Deoxyribonucleic acid: DNA -- where genetic information is stored

Ribonucleic acid: RNA: transfers the genetic information to ribosomes (inside cells) where protein synthesis takes place

Good luck on

ALL