Organic Chemistry Mrs. Hanellin

March 16th through March 27th

This assignment and the LINKS FOR THE VIDEOS CAN BE FOUND ON MY WEBSITE

Disclaimer: With COVID-19 and school closings in full effect, we will be learning the organic chemistry unit from a distance.

Introduction – Organic chemistry is the study of molecules made up of carbon, hydrogen, oxygen, and nitrogen. Organic compounds form the basis of all life on earth. They are also used as the basis of pharmaceuticals, plastics, fuels, and explosives.

By the end of this unit, you will learn the following concepts:

1. Organic compounds contain carbon atoms which bond to one another in chains, rings, and networks to form a variety of structures.

2. Organic compounds are named using the IUPAC system (included in Table P, Q and R)

3. Hydrocarbons are compounds that contain only carbon and hydrogen. Saturated hydrocarbons contain only single bonds between carbon atoms. Unsaturated hydrocarbons contain at least one double or triple bond between carbon atoms.

4. Other categories of organic molecules include: organic acids, alcohols, esters, aldehydes, ketones, ethers, halides, amines, amides, and amino acids. Each of these types have different properties. (Table R)

5. Some organic molecules have the same molecular formula; however, their atoms are arranged in different ways. These are called isomers.

6. In a multiple covalent bond (double or triple bond), more than one pair of electrons are shared between two atoms. Unsaturated organic compounds contain at least one double or triple bond. (examples in Table Q)

7. Types of reactions that involve organic molecules include: addition reactions, substitutions, polymerization, esterification, fermentation, saponification, and combustion.

Topic 1: Naming and drawing saturated hydrocarbons (alkanes)Day 1

I. Watch the video assigned on Khan academy titled “Representing structures of organic molecules” (7 minutes)

II. Answer the following questions while watching the video:1. Organic chemistry is dealing with chains of __________2. Each bond consists of __ electrons

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3. The simplest way to draw an organic molecule is with a _____ ________ diagram. This is also known as a structural formula.

4. Each end point or angle in this diagram represents a ________ atom.5. It is assumed that the rest of the bonds not shown are with _________ atoms.

Day 2

III. Watch the video assigned on Khan academy titled “Naming simple alkanes” (9 minutes)

IV. Answer the following questions while watching the video:1. If an organic molecule has a backbone consisting of 3 carbon atoms, what is

the prefix going to be? _____ -2. If there are no double bonds in the hydrocarbon, the ending of the name

ends in -____3. A hydrocarbon with 7 carbons and only single bonds, its name would be

___________4. If the carbon atoms are in a ring structure, its name starts with the prefix

______-5. Nine carbons in a ring is called ___________6. Try drawing cyclohexane below:

Day 3

V. After watching the two assigned videos, answer the following questions: (remember, you can always go back and re-watch the videos!)

1. Consider the formulas for of the first few alkanes: methane is CH4, ethane is C2H6, and propane is C3H8. Given the pattern represented by this series, predict the formula of an alkane with 4 carbons. Use Tables P and Q to help you! ___________

2. Try drawing a structural formula for this 4-carbon alkane below: (look at Table Q for examples of what structural formulas should look like).

3. What is the general formula for alkanes found in Table Q? ___________4. What does “n” represent in this formula? __________5. For a 5-carbon alkane:

If n=5, then 2n+2=12. So, the formula is __________

6. Using the general alkane formula, predict molecular formulas for the rest of the ten alkanes:

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i. C6 _____________

ii. C7 _____________

iii. C8 _____________

iv. C9 _____________

v. C10 _____________

7. Each name of an alkane is composed of a prefix (which indicates the number of carbon atoms in the backbone carbon chain), and is followed by the alkane family suffix “-ane.”

This means that: meth- means one carbon atom.eth- means two carbon atomsprop- means threeBut- means four.____- means fiveHex- means ______Hept- means ___________-means eightNon- means _________- means ten.

8. Draw structural formulas for butane and pentane, using the “CnH2n+2” alkane general formula.

Butane: Pentane:

9. Name the following alkanes below and write molecular formulas:

i. (example) CH3CH2CH2CH3 Butane C4H10

ii. CH3CH2CH2CH2CH2CH2CH3 _______________ ______________

iii. CH3CH2CH2CH2CH3 _______________ ______________

10. Write the molecular formula of an alkane containing 25 carbon atoms:

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11. What is the molar mass (gram-formula mass) of the alkane C6H14?

12. Challenge yourself! These molar masses represent certain alkanes. Figure out which ones they are. Give the name and draw the structural formula for each.

Name Structural formula30 g/mol

58 g/mol

114 g/mol

VI. Finally, answer these common Regents questions:

1. Which two terms represent types of chemical formulas?i. Mechanical and structural

ii. Mechanical and thermaliii. Molecular and structuraliv. Molecular and thermal

2. The only two elements found in alkanes arei. Carbon and nitrogen

ii. Carbon and hydrogeniii. Oxygen and nitrogeniv. Oxygen and hydrogen

3. The atoms of which element bond to one another in chains, rings, and networks?

i. Bariumii. Carboniii. Iodineiv. Mercury

4. What is the chemical name for the compound CH3CH2CH2CH3?

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Topic 2: Isomers of alkanesDay 4

I. Read this definition of isomers: Molecules with the same molecular formula, but different structures and different chemical properties. In other words, isomers are compounds that have the same number and kind of atoms in their molecules, but the atoms are arranged in different sequences.

II. Question: Below, are three isomers of pentane. Why are all 3 considered to be varieties of pentane? They all have the same _____________ formulas but different ___________.

III. IMPORTANT NOTE 1: Notice that some of these isomers have “branches” or carbon atoms coming off of the main chain of carbons. We call these branches “alkyl” groups. In the middle structure pictured above, there is a single carbon branch attached to the 4-carbon chain. A single carbon branch is called methyl, a 2-carbon branch is called ethyl, etc… (use Table P for the rest of the prefixes).

IV. IMPORTANT NOTE 2: Sometimes substituent groups (branches) of a particular type show up more than once on the longest carbon chain. In this case, we use a naming trick, as seen on the structure to the right above. Instead of naming the compound 2-methyl, 2-methyl propane, it is named 2,2-dimethyl propane. The “di-“ before methyl just means there are 2 methyl branches in the molecule.

V. Watch the video assigned on Khan academy titled “Naming alkanes with alkyl groups” (11 minutes)

VI. Answer the following questions while watching the video:1. In this video, Khan draws 3-methyl nonane using the line-angle method. In

the space below, draw the same molecule using the structural formula technique (again, examples of what a structural formula looks like is in

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Table Q).

2. What is the difference between “3-methyl nonane” and “4-methyl nonane”?

VII. Watch the video assigned on Khan Academy titled “Correction – 2-propylheptane should never be the name!”1. Explain why 2-propylheptane should never be the name:

Day 5

VIII. After watching the two assigned videos, answer the following questions: (remember, you can always go back and re-watch the videos!)

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Topic 3: Naming and drawing unsaturated hydrocarbons (alkenes and alkynes)Day 6

I. Read the following information given below:

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II. Watch the video assigned on Khan Academy titled “Alkene nomenclature” (0:00-5:53)

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III. Now try these:

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Day 7

I. Answer the following practice regents problems:

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