metal + water metal hydroxide + hydrogen...
TRANSCRIPT
Year 11 ChemistryCovalent Bonding and Organic Chemistry
Notes and Worksheets
1
Name: __________________________________
Form Group: __________
Covalent Bonding Notes (Molecules and Lattices)
Part A: Covalent Bonding
Covalent compounds can be formed when non-metals are chemically combined. Each atom shares its electrons with others. These shared electrons form the ‘glue’ that holds the atoms together.
In general, covalent compounds: are usually liquids or gases at room temperature have low melting and boiling points do not conduct electricity and heat
Covalent bonds can form between a small number of atoms to form small molecules such as carbon dioxide (CO2) a large number of atoms to form giant molecules such as plastics an infinite number of atoms to form giant lattices such as graphite, diamond and glass
To understand the bonding of covalent compounds, the outer shell electron arrangement (configuration) must be studied.
Atom Outer shell electron arrangement Atom Outer shell electron
arrangementHydrogen Carbon
Nitrogen Oxygen
Fluorine Sulfur
Chlorine Phosphorus
These atoms generally combine in such a way that they all ‘have’ 8 electrons in their outer shell with the exception of hydrogen which only requires two.
2
Rules for drawing electron dot diagrams for molecules:
Draw electron dot diagrams for each atom in the molecule. Unpaired (bonding) electrons are available for sharing. Paired electrons (lone pairs) do not participate in bonding. Atom with the most bonding electrons is placed in the middle. All electrons must be paired – each atom (except hydrogen) must have 8 electrons around it.
All discrete molecules have a definite 3D shape. When looking at shape, we discuss the position of atoms, but lone pairs determine the shape of the molecule.
Molecule Electron dot diagram
Valence Structure Structural Formula Shape
Hydrogen H2
Nitrogen N2
Water H2O
Methane CH4
Chloromethane CH3Cl
Ammonia NH3
3
Looking at the above molecules on page 3, the number of covalent bonds needing to be formed for individual atoms to become stable can be generalised as:
AtomNumber of
covalent bonds formed
HydrogenOxygen
NitrogenCarbon
Naming molecules
Molecular formulae tell you how many atoms and of what type exist in the molecule.
E.g. Water H2O is made up of 2 hydrogens and 1 oxygenThe ‘technical’ name for water is dihydrogen oxide.
Name the following molecules:
HCl
SO2
N2O5
CO
4
mono-di-tri-tetra-penta-hexa-hepta-octa-nona-deca-
Bonding between molecules
The covalent bonds within a molecule are very strong and hard to break - this is known as an intramolecular bond. However, there is also bonding occurring between molecules - this is known as an intermolecular bond.
Intermolecular bonds are very weak in comparison to intramolecular bonds - they account for the fact that so many covalent compounds are found as gases or liquids at room temperature.
We will investigate intermolecular bonding and electronegativity in more detail later in this topic.
The properties of molecular substances
Property Molecular substances ExplanationMelting and boiling points Very low to moderate Weak forces between molecules
are easy to breakHardness of solid Very soft to moderately hard Weak forces between molecules
are easy to breakMalleability of solid Tends to be malleable rather than
shatterMolecules can rearrange themselves
Electrical conductivity Non-conductors as solid and liquid
No free moving charged particles.
5
Part B: Covalent Lattices
Three types:
- Diamond- Graphite- Bucky balls
Diamond (covalent network lattice)
Hardest known substance Composed entirely of carbon atoms Each carbon is covalently bonded to 4 other carbon atoms in a tetrahedral arrangement.
Properties of diamond Hard, since strong covalent bonds are continuous throughout the lattice, therefore has a high melting
temperature. Does not conduct electricity, as there are no free moving charged particles. Chemically inert, insoluble in water and most other solvents
Uses of diamond Jewellery Used as an abrasive for sawing, cutting and grinding Drill tips
Structure of diamond Structure of graphite
6
Graphite (covalent layer lattice)
Oily, black, opaque solid with a metallic sheen Composed entirely of carbon atoms Each carbon is covalently bonded to 3 other carbons in the same plane.
Forms layers of hexagonal rings with strong covalent bonds in 2D. Extra valence electrons are delocalised and are free to move throughout graphite layer. Layers are stacked on top of each other and are held together by weak intermolecular forces.
Properties of graphite Soft and flaky and feels slippery, as weak intermolecular forces allow layers to slide over each
other. High melting point - strong covalent bonds within layers. Good conductor of electricity - delocalised electrons are free to move throughout layers. Lustrous - delocalised electrons reflect light.
Uses of graphite 'Lead' pencils Electrodes in torch cells Tennis racquets and fishing rods
Buckyballs
Another form of carbon, where 60 carbon atoms are found in a soccer ball arrangement.
Diamond, graphite and buckyballs are all allotropes of carbon – each molecule is composed entirely of the same element, but have very different structures and properties.
ELECTRONEGATIVITY - Classifying Bond Type
The modern definition of electronegativity is due to Linus Pauling, who defines it as:
a measure of an elements attractive power for electrons in a molecular bond.
Pauling was able to develop a numerical scale of electro negativities. Below are ten common elements with their values (no units).
F 4.0 C 2.5
O 3.5 S 2.5
Cl 3.0 H 2.1
N 3.0 Na 0.9
Br 2.8 K 0.8
When you examine a periodic table, you will find that (excluding the noble gases) the electronegativity values tend to increase as you go to the right and up. The reverse statement is that the values tend to decrease going down and to the left. This pattern will help when you are asked to put several bonds in order from most to least ionic without using the values themselves.
Electronegativity values are useful in determining if a bond is to be classified as non-polar covalent, polar covalent or ionic.
What you should do is look only at the two atoms in a given bond. Calculate the difference between their electronegativity values. Only the absolute difference is important.
BOND TYPE
Non-Polar Covalent: This type of bond occurs when there is equal or symmetrical sharing (between the two atoms) of the electrons in the bond. Molecules such as Cl2, H2 and F2 are the usual examples.
Polar Covalent: This type of bond occurs when there is unequal or asymmetrical sharing (between the two atoms) of the electrons in the bond. Molecules such as NH3 and H2O are the usual examples.
Ionic: This type of bond occurs when there is complete transfer (between the two atoms) of the electrons in the bond. Substances such as NaCl and MgCl2 are the usual examples.
ELECTRONEGATIVITY RULES
Ionic Bonding – LARGE difference in electronegativityPolar Covalent Bonding – MODERATE difference in electronegativityCovalent Bonding – SMALL difference in electronegativity
Using the Pauling scale of electronegativity and your knowledge of the periodic table, predict whether the following bonds are polar or non-polar and draw an arrow to represent bond dipoles where they are present.
Direction of Bond Arrow? Polar or Non-Polar?
H I
C H
C C
O H
N H
Classify the following molecules and compounds as either ionic, polar covalent, or non-polar covalent and explain your answer:
NameFormula(you put this in)
Bond Type Explanation
Hydrogen Chloride
Potassium Bromide
Fluorine Molecule
Shapes of Covalent Molecules
Sketch the shape of the following molecules (linear, pyramidal, v-shaped, trigonal planar or tetrahedral), and use your knowledge of electronegativity to draw bond dipoles for each and predict whether it is polar or non-polar.
Molecule Diagram of Molecule Shape Polar or Non-Polar?
HBr
SiH4
CS2
H2S
CH3F
SF2
SiF4
CH3Br
Molecular Shape and Polarity
The general approach for simple molecules is to start with a Lewis dot diagram for the molecule. 1. If there are more than two atoms, focus on the central atom in the molecule. 2. Count the number of atoms bonded to the central atom.3. Then count the number of unbonded pairs of electrons on the central atom. 4. Determine the molecular shape according to the table below:
Central AtomBonded Atoms Lone Pairs Shape of Molecule
1 Any number Linear2 None Linear2 1 or more Bent3 None Trigonal Planar3 1 Pyramidal4 none Tetrahedral
MOLECULE POLARITY
After determining the shape of the molecule, look at whether the atoms surrounding the central atom are all identical to one another (for some shapes this additional step is not necessary).
Molecule Shape Are all ‘outside’ atoms identical?
Molecular Polarity
Linear Yes Non-polarNo Polar
Bent - Polar
Trigonal Planar Yes Non-polarNo Polar
Pyramidal - Polar
Tetrahedral Yes Non-polarNo Polar
Physical Properties
Metallic, Covalent and Ionic Substances
Electrical ConductivityType of bonding Melting Hardness Solid Liquid Solubility
point in water
Metallic High Varies Good Good InsolubleIonic High Hard Poor Good SolubleCovalent Molecular Low Soft Poor Poor Varies
Molecule Polarity
1. Make up each of the molecules below: Take care to select the plastic atom model with the correct configuration of bond places.
2. In your prac book draw up a table (using the headings below) with enough rows for the 14 molecules at the bottom of this page. Use a sharp pencil to neatly draw the structural formula for each molecule. The table in your prac book needs to have the following headings:
Systematic Name Semi-Structural Formula
Structural Formula
Polar orNon-Polar
Electronegativity Difference
3. For each molecule determine the degree of bond polarity by determining the difference of electro negativities for the two atoms in the bond. An electronegativity difference of less than 0.5 can be considered “Non-Polar”. Write this electro negativity difference next to your structural formula.
4. Decide whether the molecule itself is polar. (Use the same definition as in 3 above concerning electronegativities).
Molecules
Systematic Name Common Name Semi-Structural Formula Polarity1 Chloro - methane CH3Cl2 Methane CH4
3 Tri-chloro Methane Chloroform CHCl3
4 Hydrogen Sulfide “Rotten Egg Gas” H2S5 Tetra-chloro Methane CCl4
6 Hydroxy Methane Methanol CH3OH7 Water H2O8 Amino Methane Methylamine CH3NH2
9 Formic Acid HCOOH10 Propane CH3CH2CH3
11 Ammonia NH3
12 Ethane CH3CH3
13 1 – Hydroxy Propane 1 - Propanol CH3CH2CH2OH14 2 – Hydroxy Propane 2 - Propanol CH3CH(OH)CH3
5. Draw up a second table and redraw the molecules in groups using the following headings:
Non-Polar Molecules (based on the definitions you have used above)
Polar Molecules in order from the ones with the LEAST polar bonds to the MOST polar bonds
Model Building of Covalent Compounds
Introduction: A molecule can be represented on paper by either a molecular or a valence structure. A molecular formula indicates the number and kind of each atom present in a molecule. Some familiar molecular formulae are shown below:
H2O NH3 CH4
These molecular formulae do not provide any information concerning the actual arrangements of atom in a molecule. Such information is given by valence structures.
Aim: In this task, you will construct 3D models to help you visualise the shapes of molecules. In addition, you will draw the valence structures that represent the shapes of molecules.
Note: the valence structure shows all outer shell electrons involved in bonding as well as lone pairs.
Equipment: A model building kit will be provided.
Procedure:1. As you build the models indicated, use a sharp pencil to carefully draw the valence structure of the molecules in the space provided.2. Write the shape of each molecule when requested.
F2 H2O NH3 CH4
Shape: Shape: Shape: Shape:Cl2 H2S CCl4 CCl2F2
Shape: Shape: Shape: Shape:N2 CO2 O2 C2H2
Shape: Shape: Shape: Shape:
HCN C2H6 C4H10 (2 different structures)
Shape: Shape:
Intermolecular Forces - dispersion, dipole-dipole and hydrogen bonding
Part A: Intermolecular Bonding
We can explain the forces holding molecules together in the solid and liquid phases by discussing three models of intermolecular bonding:
Dispersion forces Dipole-dipole interactions Hydrogen bonding
Note that all of these bonding models are much weaker in nature than the covalent bonds that hold the atoms together in the molecules. Hence, when heat is applied, these weaker bonds between molecules are disrupted and the molecule melts or boils. The strong covalent bonds between atoms within the molecule remain intact.
Molecules are not charged, but some behave like they are!
When two different non-metal atoms form a covalent bond, one atom usually attracts the bonding electrons more strongly than the other atom. The atom that has the great pull on the electrons is said to have a higher electronegativity.
The electronegativity of an element is a measure of the relative attraction that the element has for electrons in a bond. It is often referred to as the electron pulling power of an atom.
The electronegativity of the elements tends to increase from left to right across a period of the Periodic Table and to decrease down a group.
Why do the non-metals have higher electronegativities than the metals? ______________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
Why do the Noble Gases have undefined electronegativities? ________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
Because some elements are more electronegative than others, this has an effect on the shared electrons in a covalent molecule.
Use a pencil to neatly and carefully draw the structural formula for a molecule of hydrogen chloride. Show any bonding and non-bonding electron pairs and also the polarity of any bonds.
The bonding electrons are shared unequally and move closer to the more electronegative atom. This will have the effect of making the more electronegative atom appear as if it had a negative pole and the less electronegative atom appear as if it had a positive pole. A bond dipole develops. This is known as a polar bond.
One would expect the larger, stronger creature to win the tug-of-war. A polar covalent bond occurs when one atom is able to “pull” electrons to it more easily than another atom.
If 2 atoms have an equal pull on the shared electrons, a non-polar bond is formed.
Use a pencil to neatly and carefully draw the structural formula for a molecule of fluorine. Show any bonding and non-bonding electron pairs and also the polarity of any bonds.
One would expect that “twins” would be evenly matched in a tug-of-war. A non-polar covalent bond occurs when two atoms have an equal “pull” for shared electrons.
Are the following bonds polar or non-polar?
E.g. H2 E.g. ClF
A polar molecule is formed if
the molecule contains dipoles (polar bonds)
A non-polar molecule is formed if
the molecule does not contain dipoles (polar bonds)
Dipole-dipole interactions
These forces of attraction occur between polar molecules such as HCl where the negative pole on one molecule is attracted to the positive pole on another molecule. They form relatively strong attractive forces between molecules (but still weak compared to the covalent bonds between the atoms.
Generally, the greater the dipole, the stronger the polar attraction between the molecules, the stronger the intermolecular bonding and the higher the melting point.
Hydrogen bonding (remember the acronym H-ONF)
Hydrogen bonding is a special type of dipole-dipole bond. When the three most electronegative atoms known – oxygen, nitrogen and fluorine – are bonded to a hydrogen atom, the largest possible dipole is set up within the molecule. Hence, molecules such as H2O, NH3 and HF tend to have the strongest forces of attraction between the molecules and this is reflected in their melting temperatures.
Hydrogen bonding is the strongest of the three forms of bonding between molecules and is observed in molecules containing –OH (alcohols) and –NH2 (amines) groups attached to them.
Hydrogen bonding can explain the special properties of water:
26
H-bonds between base pairs in DNA
High melting and boiling points Expansion on freezing These properties will be addressed in more detail Excellent solvent later in the Unit.
27
Dispersion forces
Dispersion forces are the weakest of all intermolecular forces. They operate between all covalent molecules, and they arise because of the constant movement of electrons within atoms. These forces are thought to be electrostatic in nature. This movement of electrons will result in an instantaneous dipole. These temporary dipoles can attract each other but because they are not permanent, the attraction is weak. The strength of dispersion forces depends on the number of electrons in the molecule and the shape of the molecule.
Dispersion forces are also responsible for the attraction between the hexagonal layers in graphite.
The strength of the intermolecular bonds in operation will determine the melting and boiling point of that substance.
Order of strength of intermolecular bonding
Hydrogen bondingDipole-dipole interactions Decreasing strengthDispersion forces
Note that these intermolecular forces are significantly weaker than the forms of bonding (metallic, ionic, covalent molecular, covalent network lattice, covalent layer lattice) previously studied.
28
Investigating Intermolecular Bonding (Melting Temperature vs Molar Mass)
Non-metal atoms will bond with other non-metal atoms by sharing electrons forming covalent bonds and clumping the atoms together into molecules. These bonds are described as intramolecular forces (intra being in between atoms) and are considered to be very strong.
However what holds molecules together in solid and liquid phases is another classification of bonding altogether. These are described as intermolecular forces, and are much weaker than the covalent bonds between atoms. There are three types of intermolecular forces:
1. Dispersion forces
2. Dipole-dipole forces
3. Hydrogen bonding
You will be looking at what effect these intermolecular forces have on a particular property of materials – their melting temperature.
Procedure:
1. Use a sharp pencil and a ruler to carefully plot a graph of - Melting Temperature vs Mass of Molecules – for the sets of data supplied (page 30). Plot these four (4) graphs on the same set of axes. Use a different colour for each set of data.
2. The mass of the molecule can be calculated using the atomic masses from the Periodic Table.
eg. HCl one hydrogen atom 1.0one chlorine atom 35.5mass of HCl 36.5
eg. GeH4 four hydrogen atoms 4 x 1.0 = 4.0one germanium atom 72.6mass of GeH4 76.6
3. Use a scale range of –200 C to 0 C for temperature and 0 to 150 for Molecular Mass.
Preliminary Questions:
1. What does the word hydride mean? _____________________________________________
________________________________________________________________________________
29
2. Apart from being covalently bonded to hydrogen, what have all the other non-metals have in common in each set of data? (Clue: refer to your periodic table)
_____________________________________________________________________________
_____________________________________________________________________________
3. Explain, in terms of electron bonding arrangements, why the Group XVII hydrides are bonded to only one hydrogen, the Group XVI hydrides are bonded to two hydrogens, the Group XV hydrides are bonded to three hydrogens and the GroupXIV hydrides are bonded to four hydrogens.
____________________________________________________________________________
____________________________________________________________________________
Discussion Questions:
1. Do any molecules deviate from the trend shown in any of the graphs? If so, explain how they deviate and why, in terms of intermolecular and the polarity of molecules.
____________________________________________________________________________
____________________________________________________________________________
____________________________________________________________________________
2. Which group does not have any molecules deviating from the trend? Explain your answer by discussing intermolecular forces and the overall polarity of molecules.(Clue: don’t forget symmetry.)
____________________________________________________________________________
____________________________________________________________________________
____________________________________________________________________________
30
DATA
Graph 1: Group XVII Hydrides
Molecule Molar Mass Melting Temperature (oC)
HF - 83
HCl - 114
HBr - 87
HI - 51
31
Graph 3: Group XV Hydrides
Molecule Molar Mass Melting Temperature (oC)
NH3 - 78
PH3 - 134
AsH3 - 116
SbH3 - 88
Graph 2 Group XVI Hydrides
ORGANIC CHEMISTRY
Refer to the appropriate chapter in your textbook to help you fill in the blanks.
Organic chemistry refers to compounds containing ________________________
The electronic configuration of carbon = _________________ or __________________________
Carbon atoms form strong ____________________________ bonds with other carbon atoms
Molecule Molar Mass Melting Temperature (oC)
H2O 0
H2S - 86
H2Se - 66
H2Te - 51
Graph 4: Group XIV Hydrides
Molecule Molar Mass Melting Temperature (oC)
CH4 - 183
SiH4 - 185
GeH4 - 166
SnH4 - 150
Hydrocarbons are compounds that contain carbon and hydrogen. Two common families of hydrocarbons are alkanes and alkenes.
A homologous series is ____________________________________________________________
_______________________________________________________________________________
The corresponding molecular formula and names of the first ten alk-Anes are:
Formula Name
1. ________ _______________
2. ________ _______________
3. ________ _______________
4. ________ _______________
5. ________ _______________
6. ________ _______________
7. ________ _______________
8. ________ _______________
9. ________ _______________
10. ________ _______________
General molecular formula for alkanes = _____________
True or false? - carbon atoms in alkanes form single bonds with four other atoms
The names and structural formula for the first three alkanes are:
There are ____________ possible structural formula for butane. These are:
An isomer is ____________________________________________________________________
_______________________________________________________________________________
A saturated hydrocarbon is ________________________________________________________
_______________________________________________________________________________
An unsaturated hydrocarbon is ____________________________________________________
Name ________________ Name ________________ Name ________________
Straight-Chain Molecule Branched-Chain Molecule
_______________________________________________________________________________
The corresponding molecular formula and names of the first nine alk-Enes are:
Formula Name
1. ________ _______________
2. ________ _______________
3. ________ _______________
4. ________ _______________
5. ________ _______________
6. ________ _______________
7. ________ _______________
8. ________ _______________
9. ________ _______________
General molecular formula for alkenes = _____________
True or false? - there is one double carbon-carbon bond in alkenes
Are alkenes saturated of unsaturated hydrocarbons? __________________________
The structural formula for propene is:
Draw the three (3) isomers of butene are:
Are hydrocarbons polar or non-polar? ______________________________________
What sort of bonding exists between the atoms of hydrocarbons? _________________________
Because hydrocarbon molecules are ________________, ________________________________
forces exist between them.
_______________________________ are ___________________________________ forces
which increase in strength as the size of the molecules increases.
As the size of hydrocarbon molecules increases, boiling temperature _______________________
because ________________________________________________________________________
_______________________________________________________________________________
Structural Models of Hydrocarbons
Aim: 1. To build models of hydrocarbon molecules2. To study the relationship between the 3D models and the structural formulae of
hydrocarbons3. To construct models of isomers
Procedure:
A. Linear and branched alkanes
1. Make a model of methane, CH4, and sketch it.2. Make a model of propane, C3H8, and sketch it. Can this molecule be rearranged to form a
different molecule? If so, sketch and name it.
3. Make a model of pentane, C5H12. Construct as many isomers as you can, and draw a valence structure for each molecule. Name each structure.
B. Alkenes
4. Make a model of ethene, C2H4, and sketch it.5. Make a model of butene, C4H8, and sketch it. Can this molecule be rearranged to form
different molecules? If so, sketch and name them.
C. Alkynes
6. Make a model of ethyne, C2H2, and sketch it.
1. 2.
3. 4.
5. 6.
FUNCTIONAL GROUPS
A functional group is ______________________________________________________________________
_______________________________________________________________________________________
A hydroxy functional group has the formula = ______________
Compounds that contain a hydroxy group are known as ________________________
The names of the first ten alcohols are:
1. ____________________
2. ____________________
3. ____________________
4. ____________________
5. ____________________
6. ____________________
7. ____________________
8. ____________________
9. ____________________
10. ____________________
Alcohols are polar or non-polar __________________ because ___________________________
_______________________________________________________________________________
_______________________________________________________________________________
What two intermolecular forces act between alcohol molecules?
1. _____________________________________
2. _____________________________________
Why are the boiling temperatures of alcohols higher than for alkanes and alkenes? ___________
_______________________________________________________________________________
_______________________________________________________________________________
Naming Hydrocarbons
Butane Propene
Ethene 2-methylpropane
Pentane 2-methylpropene
3-methyl but-1-ene 2-pentene
2,3-dimethylbutane 2,2-dimethyl propane
Naming Hydrocarbons
2-methyl-4-ethyl heptane But-1-ene
But-2-ene 5,5-dimethyl hept-3-ene
3-ethyl pentane 2-methyl pentane
2,2-dimethyl butane 2,3-dimethyl butane
2-methyl hex-3-ene 2,2,3-trimethyl butane
Naming Hydrocarbons
2-methyl-4-ethyl heptane Ethanoic acid
Ethane Nonene
3-propyl-dec-4-ene Methene
2-methyl pentane 3-ethyl-2-methyl pentane
3-ethyl hexane 4,5,5-trimethyl oct-2-ene
Naming Hydrocarbons
3-ethyl hex-2-ene 2,4-dimethyl hex-4-ene
3-methyl oct-2-ene 3-ethyl pentane
Naming and Drawing Organic Molecules
PART A: Use a sharp pencil to accurately draw the following molecules in the spaces provided.
Heptane 2,3-dimethylbutane
2,2 -dimethyl,4-ethylhexane 3-methylpent-2-ene
2,2-dichloro,3-methylpentane 3,4,6-trifluoro,5-iodooct-3-ene
Pentanoic acid Heptanol
1,2-dibromobenzene Cyclobutane
PART B: Write the systematic name underneath each of the following molecules.
Organic Nomenclature
1. Draw each of the following organic compounds.
(a) 3-methylpentane (b) 2,2-dimethylhexane(c) 2,3-dimethylbutane (d) 3,3,4,4-tetramethylhexane(e) 4-ethyl-3-methylheptane (f) 2,3,4-timethylhexane(g) 2,2,3-trimethyloctane (h) 4-methyl-1-hexene(i) 2,3-dimethyl-1-butene (j) 2-methyl-1-pentene
2. Draw each of the following organic compounds.
(a) 2,3-dimethylbutane (b) 1,3-dichloro-2-pentene(c) 2,2-dibromo-5-methylhexane (d) 2-pentanol(e) 2,2-diiodopropane (f) 1-bromo-2-chloro-4-iodo-2-butene(g) 4-iodo-2-pentanol (h) Pentyl butanoate(i) 2,3,5,6-tetramethyloctane (j) 3-bromo-1-hexanol(k) 4-methyl hexanal (l) 2-butanamine(m) 1-fluoro-2-pentene (n) 3-methylbutanoic acid(o) 2-chloro-3-ethylpentane (p) 2-pentanone(q) 4,4-dimethyl octanal (r) 2,3-dichloropropanoic acid(s) 4-bromo-1-butene (t) Propyl Propanoate
3. Name the following organic compounds systematically:
1) 2)
3) 4)
5) 6)
7) 8)
9) 10)
11) 12)
13) 14)
15) 16)
17) 18)
19) 20)
4. This question relates to the organic compounds in part 3 above:
(a) On each of the organic compounds highlight and name the functional groups present.
(b) Mark the organic compounds that are saturated hydrocarbons with an asterisk.
(c) Which of the above would possess a sweet fruity odour and be insoluble in water?
5. The following questions relate to the organic compounds below:
A. CH3CH2OH B CH2CHCH3 C CH3CH3
D CH3CH2CH2CH2NH2 E CH3COO(CH2)3CH3 F CH3COOH
G CH3(CH2)7CH3 H CH2ClCF3
a) Describe how, if you were given samples of B (an alkene) and C (an alkane), you could chemically
distinguish between them in the laboratory.
_____________________________________________________________________________________
_____________________________________________________________________________________
b) (i) Which compound above is an 'unsaturated hydrocarbon'? _________________________________
(ii) Name the reagent which would be required to convert the above 'unsaturated hydrocarbon' into a
‘saturated hydrocarbon’. ___________________________
(iii) Name the type of chemical reaction undergone by this 'unsaturated hydrocarbon' above.
__________________________________________
(c) Which compound/s is/are a chlorofluorocarbon (CFC)? _____________________________
6. (i) In the space below use a pencil to neatly and carefully draw one primary, secondary and tertiary
alcohol with the molecular formula C4H9OH.
(ii) What term is given to organic compounds with the same molecular formula, but a different structural
formula?
________________________________
7. State what you would observe if an alkene is shaken with some bromine water. __________________
_____________________________________________________________________________________
8. Shown below is the condensed structural formula of an ester:
CH
H
H
C
O
O C
H
H
C
H
H
C
H
H
H
CH
H
H
C
O
O C
H
H
C
H
H
C
H
H
H
(i) Name the ester __________________________________________________________
(ii) What type of odour would this ester possess? ____________________________________________
(iii) Predict whether this ester is soluble or insoluble in water ______________________________
(iv) Write down the structural formula and name for the alcohol and the carboxylic acid used in making
this ester.
Alcohol ___________________________________
Carboxylic Acid ___________________________________
9. The compound (A), whose structural formula appears below, has been isolated as a flavour constituent of grape juice.
(i) Name the functional groups other than the aromatic ring present in (A).
_____________________________________________________________________________________
_____________________________________________________________________________________
10. The Mediterranean fruit-fly is attracted to the substance Trimedlure. This is used commercially in
baited traps to capture the Mediterranean fruit-fly. Trimedlure has a structure similar to the one shown
below:
(i) Would you expect Trimedlure to be water soluble? Explain your answer. _______________________
_____________________________________________________________________________________
_____________________________________________________________________________________