Department of Chemistry

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• Department of Chemistry
• CHEM1020 General Chemistry
• Instructor Dr. Hong Zhang
• Foster Hall, Room 221
• Tel [phone]
• Email hzhang_at_tntech.edu

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CHEM1020/General Chemistry_______________________
__________________Chapter 9. (L6)-Organic
Chemistry

• Todays Outline
• ..Aldehydes
• ..Ketones
• ..Carboxylic acids

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Chapter 9. (L6)-Organic Chemistry

• Are atoms and molecules real? Are the structures
  of atoms and molecules real?
• ..Einsteins analogy about the meaning of
  scientific theories and models
• The analogy of closed watches
• electronic vs. mechanic
• From Albert Einstein and Leopold Infeld, The
  Evolution of Physics, From early concepts to
  relativity and quanta, 1938.

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Chapter 9. (L6)- Organic Chemistry

• Einsteins analogy about the meaning of
  scientific theories and models
• Physical concepts are free creation of the human
  mind, and are not, however it may seem, uniquely
  determined by the external world. In our endeavor
  to understand reality we are somewhat like a man
  trying to understand the mechanism of a closed
  watch. He sees the face and the moving hands,
  even hears its ticking, but he has no way of
  opening the case. If he is ingenious he may form
  some picture of a mechanism which could be
  responsible for all the things he observes, but
  he may never be quite sure his picture is the
  only one which could explain his observations. He
  will never be able to compare his picture with
  the real mechanism and he cannot even imagine the
  possibility or the meaning of such a comparison.
  But he certainly believes that, as his knowledge
  increases, his picture of reality will become
  simpler and simpler and will explain a wider and
  wider range of his sensuous impressions. He may
  also believe in the existence of the ideal limit
  of knowledge and that it is approached by the
  human mind. He may call this ideal limit the
  objective truth. From Albert Einstein and
  Leopold Infeld.

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Chapter 9. (L6)-Organic Chemistry

• Review of electronic structure of oxygen
• Review of electronic structure of oxygen
• Valence electronic structure of O
• ..
• O or O
• ..
• O can have two unpaired electrons available for
  bonding with C to form a double bond

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Chapter 9. (L6)-Organic Chemistry

• Carbonyl group
• ..O can have two unpaired electrons available
  for bonding with C to form a double bond
• O
• or CO
• -C-
• This is a type of new functional group, called
  carbonyl group

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Chapter 9. (L6)-Organic Chemistry

• Aldehydes
• Aldehydes are the hydrocarbons with the
  following functional group O
• R-C-H
• Thus, the following is the specific functional
  group for aldehydes
• O
• or
  -CHO
• -C-H

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Chapter 9. (L6)-Organic Chemistry

• Aldehydes
• Examples of aldehydes
• The simplest aldehyde
• HCHO O formaldehyde
• H-C-H
• a gas at room T, ready soluble in water,
• a 40 solution is called formalin, used as a
  preservative for biological specimens and also
  used in embalming fluid.
• it is also used in making certain plastics.
• it is also used to disinfect homes, ships, and
  warehouses.

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Chapter 9. (L6)-Organic Chemistry

• Aldehydes
• Examples of aldehydes
• The simplest aldehyde
• HCHO O formaldehyde
• H-C-H
• formaldehyde can be made commercially via the
  following reactions through oxidation
• CH3OH ? HCHO

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Chapter 9. (L6)-Organic Chemistry

• Aldehydes
• Examples of aldehydes
• acetaldehyde
• CH3CHO O
• CH3-C-H
• acetaldehyde can be made commercially via the
  following reactions through oxidation
• CH3CH2OH ? CH3CHO

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Chapter 9. (L6)-Organic Chemistry

• More examples aldehydes
• CH3CH2CHO, propionaldehyde
• CH3CH2CH2CHO, butyraldehyde
• Benzaldehyde, CHO

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Chapter 9. (L6)-Organic Chemistry

• Ketones
• Ketones are the hydrocarbons with the following
  functional group and structure O
• R-C-R
• or O
• R-C-R

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Chapter 9. (L6)-Organic Chemistry

• Ketones
• Examples of ketones, R -CH3
• O
• CH3-C-CH3 acetone
• Acetone is a common solvent for such substances
  as fats, rubbers, plastics, varnishes

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Chapter 9. (L6)-Organic Chemistry

• Ketones
• Examples of ketones, R -CH3, R -CH2CH3
• O
• CH3-C-CH2CH3 ethyl methyl ketone
• O
• CH3-CH-CH2-C-CH3 isobutyl methyl ketone
• CH3

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Chapter 9. (L6)-Organic Chemistry

• Carboxylic acids
• Carboxylic acids are the hydrocarbons with the
  following functional group and structure
  O
• carboxyl group
• -C-OH or -COOH
• General formula
• O
• R-C-OH or RCOOH

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Chapter 9. (L6)-Organic Chemistry

• Carboxylic acids
• Examples of carboxylic acids
• R -H, formic acid
• O
• H-C-OH or HCOOH
• or methanoic acid
• first obtained by destructive distillation of
  ants

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Chapter 9. (L6)-Organic Chemistry

• Carboxylic acids
• Examples of carboxylic acids
• R -CH3, acetic acid
• O
• CH3-C-OH or CH3COOH
• or ethanoic acid
• vinegar, 4-10 acetic acid solution

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Chapter 9. (L6)-Organic Chemistry

• More example of carboxylic acid
• O
• Benzoic acid C-OH
• sodium benzoate is used as food addictive to
  prevent mold

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Chapter 9. (L6)-Organic Chemistry

• Quiz Time
• Which of the following is an aldehyde
• (a) CH3CH2OCH2CH3
• (b) CH3OCH2CH3
• (c) CH3CH2OH
• (d) CH3CHO.

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Chapter 9. (L6)-Organic Chemistry

• Quiz Time
• Which of the following is a ketone
• (a) CH3CH2OCH2CH3
• (b) CH3COCH2CH3
• (c) CH3CH2OH
• (d) CH3CHO.

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Chapter 9. (L6)-Organic Chemistry

• Quiz Time
• Which of the following is a carboxylic acid
• (a) CH3CH2OCH2CH3
• (b) CH3COCH2CH3
• (c) CH3CH2COOH
• (d) CH3CHO.

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Chapter 9. (L6)-Organic Chemistry

• Quiz Time
• Which of the following is a propionaldehyde
• (a) CH3CH2OCH2CH3
• (b) CH3COCH2CH3
• (c) CH3CH2CHO
• (d) CH3CHO.

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Chapter 9. (L6)-Organic Chemistry

• Quiz Time
• Which of the following is a diethyl ketone
• (a) CH3CH2OCH2CH3
• (b) CH3CH2COCH2CH3
• (c) CH3CH2CHO
• (d) CH3CHO.

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Chapter 9. (L6)-Organic Chemistry

• Quiz Time
• Which of the following is acetic acid
• (a) CH3CH2OCH2CH3
• (b) CH3CH2COCH2CH3
• (c) CH3CH2CHO
• (d) CH3COOH.