Esterfication Lab

Purpose: to synthesize an ester from a carboxylic acid and an alcohol.

Materials:
-isopropyl alcohol
-methanol
-salicylic acid
-acetic acid
-concentrated sulphuric acid
-2 x 200 mL beakers
-ice
-water
-eye droppers
-test tubes

Background: esterfication is the formation of an ester from a carboxylic acid and an alcohol

Esters are responsible for many common smells.
Ester, alcohol, acid:
banana, isopentyl alcohol, acetic acid
orange, octyl alcohol, acetic acid
wintergreen, methyl alcohol, salicylic acid
raspberry, isobutyl alcohol, formic acid
pineapple, ethyl alcohol, butyric acid (smells like vomit)
pear, n-Propyl alcohol, acetic acid
rum, isobutyl alcohol, propionic acid
apple, methyl alcohol, butyric acid (smells like vomit)
pear-like, benzyl alcohol, acetic acid
perfume, isopropyl alcohol, acetic acid

Procedure:

1. For this experiment, the mixtures must be heated by a boiling hot water bath. Use a hot plate to heat up about 150 mL of water (in a beaker) for the water bath.

Methyl Salicylate

1. .
2. Add one scoop of Salicylic acid to a test tube.
3. Add 15 drops of methanol to the same test tube
4. Add 2-4 drops of Sulphuric acid(which is very corrosive)
5. Place the test tube in the hot water bath for 15 minutes and place a 10 mL beaker over the test tube.
6. Cool the test tbe in the ice water bath for 2 minutes
7. Carefully smell the test tube by wafting the fumes towards your nose.
8. If there is no apparent smell, pour the contents of the test tube into a small beaker of water and try again.

Ethyl ethanoate

1. .
2. Add 10 drops of acetic acid to a test tube.
3. add 10 drops of ethanol to the same test tube.
4. add 2-4 drops of sulphuric acid (corrosive, caution!)
5. place the test tube in the hot water bath for 15 minutes and place a 10 mL beaker over the test tube.
6. cool the test tube in the ice water bath for 2 minutes
7. carefully smell the test tube by wafting the fumes towards your nose.
8. if there is no apparent smell, pour the contents of the test tube into a small beaker of water and try again.

Observations:

We made the wintergreen scent, and it smelled like A535 lotion. It smelled delightful and swell.

May 20, 2010 Amides and Amines

AMIDES:
-use carbon prefix and -amide suffix
-building blocks of protein
-nylon, kevlar, penicillin, LSD


AMINES
-contains nitrogen with carbon chain
-alkyl prefix with -amine ending

Some examples are:

May 18, 2010

ALDEHYDES:
naming- change the -e ending to -al



CARBOXYLIC ACIDS:

-found in insect bites
-building blocks of fat/steroid
naming- change ending to -oic acid

ESTER:
-found in flavouring, perfumes, cosmetics, fruits, vegetable oil
-formed by esterfication of carboxylic acids

Name the primary chain with -yl ending
secondary chain eds in -oate

May 14 - Functional Groups

Halides

• Halogen atoms replace a hydrogen
• bromo, chloro, floro

Alcohols

• OH/ hydroxyl group
• change the ending to -ol

Ketones

• oxygen atom double bonded to carbon
• change the ending to (an) - one
  

Ethers

• Have an O joining 2 carbon chains together
• Name each carbon chain with -yl ending and add 'ether.'
  

Cyclo Alkanes & Aromatics- May 10

In todays class we learned about Cyclo Alkanes and Aromatics.

Cyclo Alkanes

-Carbon compounds can form rings
-Follow the same naming rules and add cyclo- in front of the parent chain

cyclobutane

Name:

1.
cyclopentane
2.
1 ethyl 3 methyl cyclohexane

Draw the structural diagram for:
1. 1,3,5 trimethyl cyclo octane

2. 1 ethyl 3,4 dimethyl cyclohexane

If a cyclic chain is a side chain use cyclo___yl
2 methyl 3 cyclopropyl pentane

Aromatics
When a cyclic 6 carbon chain forms it can create a resonance structure
*Benzene

Name:
1,3,5 trimethyl 2,4,6 trimethyl Benzene

If [ 0 ] is a side chain label it phenyl!

May 4 - Alkenes and Alkynes

B. Alkenes

• Compounds with double bonds end in -ene
• Put a number in front of the parent chain that indicates where the doubld bond is
• More than 1 double bond changes the parent chain slightly
  

C. Alkynes

• For compounds with triple bonds use -yne ending
• Follow all the same alkene rules
  

April 30 - Organic Chemistry

Organic Chemistry

• There are more carbon compound than all ionic compounds combine
• the study of carbon compounds is called organic chemistry
• carbon can have multiple bonds and form many different shapes

Hydrocarbons:

• Aliphatics

1. alkanes
2. alkenes
3. alkynes

• Alycyclics
• Aromatics

Hydrocarbons have 3 types of formulas:

Nomenclature of Hydrocarbons:
- one molecular formula can have a number of different structures
Isomers are compounds that can be drawn in more than 1 way
















Naming Alkanes:(all single bonds)

1. name the longest chain by using the correct suffix and add -ane
2. locate any branches by numbering carbon atoms *use the lowest possible number system
3. name branches by using appropriate suffix and -yl ending (alkyl branches)
4. if there are more than one of the same alkyl group, number each one and add the multiplier number in front of the branch name. *use alphabetical naming system.

Apr 22- Ions in Solutions

On thursday's class we learned about ions in solutions.

- The formation of a solution depends on the ability of the solute to dissolve in the solvent.
- Solvation is the interacting between solutes and solvent.
- Ionic solds are crystals made up of ions (salts)
- Molecular solids are crystals made up of neutral molecules.

- Dissolving ionic solutions produces ions in a process called dissociation
Ex. NaCl(s) --(H2O)--> Na+(aq) + Cl-(aq)
- Ionization is the break up of a neutral molecule into charged particles
Ex. CH3COOH ----> CH3COO(-) + H(+)

- Determining concentrations is relatively easy.
Ex. What is the [Cl-] in a solution of 0.50M
AgCl3 ----> Ag+(aq) + 3Cl-(aq)

What is the [NO3-] in a solution of 0.82M Fe(NO3)2?
Fe(NO)3 ----> 2Fe 2+(aq) + 2NO3-(aq)
0.83M --(X2)--> 1.64M

What is the [Cr2O7 2-] and [K+] when 3.5g is dissolved in 40mL of water?
K2Cr2O7 ----> 2K(+) + Cr2O7(2-)
294.2g/mol 3.5g divided by 294.2g/mol = 0.0119mol divided by 0.04L = 0.297M

What is the [NO3-] when 100mL of 0.6M AgNO3 is mixed with 200mL of 0.40M Mg(NO3)2?"
AgNo3 ----> A3(+) + NO3(-)
0.600M 0.600M 0.600M

April 20, 2010 Class

Intermolecular Bonds
-Bonds between molecules
-3 types



1. London Dispersion Force (L.D.F)

• Results from temporary electron dipoles (2 poles)
• Weakest intermolecular force
• Increases as # e- incrase
• occurs in any compound that has e- (ie: everything)
  

2. Dipole-Dipole Force (D.D.F)

• Results from a permanent dipole in molecules
• POLAR molecules experience this force
• Polarity depends on how much elements want e-. (electronegativity)
• Electronegativity increases right and up
• The strength of a dipole-dipole bond depends on the difference in electronegativity between the 2 atoms

F-O -> lower boiling point because less electronegativity, strength of 0.5, weaker bonds
F-N -> higher boiling point because more elecronegativity, strength 1.0, stronger bonds


3. Hydrogen Bonds (H-Bonds)

• This is a special type of dipole-dipole bond between H and O, F, or N
• Any molecule that has stronger bond with larger electronegativity difference

H-F
H-O-
HN=

Identify the substances with H-Bonds:
1. CH4 -No
2. CH30H -Yes
3. H2S -No
4. CH3-NH2 -Yes (2)
5. HCl -No
6. Yes (3)

Example: Compare the boiling Points of:
4.Ethanol(C2H5OH), 26 e- (strongest) Actual = 78
2. Ethane (C2H6), 18 e- Actual = -89
3. Methanol (CH3OH), 18 e- Actual= 65
1. Methane (CH4), 10 e- (weakest) Actual = -161

Friday April 16, 2010 Class

Polar and Nonpolar Solvents/solutes
Polar Substances have an unequal distribution of charges:


Non-polar substances have unequal charge distribution (if symmetrical)

Solution Chemistry - Mar.30

In today's class we learned about solute, solvents, solubility, saturated and unsaturated solutions.

- Solution Chemistry is the study of chemical reactions in solutions
- A solution is a homogeneous mixture
- Solvents are components present in larger amounts
- Solutes are components present in smaller amounts
- A solute is soluble (dissolves) in a solvent if it dissolves to form a homogeneous mixture
- A saturated solution contains as much solute as possible
- An unsaturated solution can dissolve more solute
- Solubility is the measure of how much solute can dissolve in a given solvent (g/L, g/mL, mol/L, ppm-parts per million)
- The solubility of Ba(NO3)2 in water is 63g/100mL @25 degrees celcius
- The solubility of Ba(NO)2 in alcohol is 1.6g/100mL @25 degrees celcius
- Effects: heat, change of solute/solvent

Example of a Saturated Solution: Water bottle with plain water
Example of an Unsaturated Solution

Atoms and Ions march 22,2010

Atoms and Ions

• Atoms are electrically neutral
• # of protons = #of electrons
• Ions have different # of protons and electrons
• Ions can be either positive (lost e-) or negative (gained e-)
• Cations = positive ion
• Anions = negative ion

Examples

• Determine how many electrons each of the ions have. What type of ion are they (cation/Anion)

Ca2+ -> lost 2e-, 18 electrons, cation

F- -> gained 1 e-, 8 electrons, anion

H+ -> lost 1e-, 0 electrons, cation

H- -> gained 1 e-, 2 electrons, anion

Examples

76 As 3- -> 33 p+, 43 n, 36 electrons (gained 3)

201 Au+ -> 79p+, 122n, 78 electrons (lost 1)

Bohr diagrams for Ions

Bohr diagrams could also be written as:

8e-
2e- 2e-
10 4
9 F 3 Li

Chemical Bonds

• A bond is an electrostatic attraction btwn particles
• Bonds occur as elements try to achieve Noble gas electron configuration
• Noble gases (usually) do not form compunds or bonds
• In Noble gases the outermost energy level have stable octets.
• Metals lose electrons (oxidize)
• Non metals gain electrons (reduced)

Lewis Dot Structure

• Atoms can be represented by dot diagrams
• Dots represent electrons
• Only Vanlence level electrons are shown
• Wtrite the atomic symbol for the atom
• -this rep. the nucleus and filled inner electron leves
• one dot is used to rep outer energy level electrons
• one e- is placed in each orbital before any pairing occurs
• - beginning with the 5th e-, pairing can occur up to a maximum of 8e-

Example

Carbon, Hydrogen, Nitrogen

Ionic Bonds (have brackets (covalent dont have brackets)

• electrons are transferred from metal to nonmental. no dots are shown on metal
• charged species is written in brackets
  

EMISSION SPECTRA - MARCH 5 CLAASS

Emission Spectra

• Each element gives of a specific colour of light
• These are known as emission spectra -Unique to each element
• If electrons absorb energy they can be bumped to a higher level
• When they fall to a lower level, they release that energy as light.
  

Atomic Structure

• Atoms are made up parts called subatomic particles
• Protons(+)
• Neutrons(neutral)
• Electrons(-)

Particle (Multiples of Proton) (Elementary Charges) Location

Mass Charge

Proton 1 1+ Nucleus

Neutron 1 0 Nucleus

Electron 1/1837 -1 Outside

Atomic Number -Number of protons

Isotopes

• The number of protons determine the type of element
• Changing the number of neutrons changes the isotope of the element.
• All isotopes have the same chemical properties

1 proton = protium

1 proton and 1 neutron = deuterium

1 proton and 2 neutrons = tritium

Mass Number

• Mass Number = total of protons and neutrons
• Symbol given is A
• Different Isotopes have different masses