In not more than three lines for each answer, briefly outline one important scientific contribution of each of the following.
a. Planck
b. de Broglie
c. Heisenberg
a. Planck is responsible for first proposing that energy is quantized. He proposed that a black body can emit or absorb electromagnetic energy E only in exact multiples of hv, giving rise to the equation E = nhv where n is a positive integer.
b. de Broglie proposed that particles can have some wavelike properties, and developed a relationship which allows the wavelength (a wave property) to be calculated from the momentum of a particle.
c. Heisenberg is responsible for the uncertainty principle which states that we cannot simultaneously know both the position (x) and the momentum (mu) of a particle exactly. There is a minimum uncertainty, h/4(pie), in their product, which is a fundamental property of matter, not an instrumental limitation.
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Chemistry Chapter 9
- Alkaloids, like morphine, caffeine, nicotine and cocaine, are heterocyclic
- Organic compounds with rings that contain atoms other than carbon are called
- Which of the following families of organic compounds does NOT contain an oxygen atom?
- Amino acids are the "building blocks" of
- Amino acids are multifunctional compounds that contain
- The reaction between a carboxylic acid and an amine yields a(n)
- Amines are
- When an amine dissolves in water the pH of the solution will be
- The compound (CH3)3N is called
- The compound CH3NH2 is called
- Amines are derivatives of
- A green chemistry improvement for the synthesis of Zoloft, an antidepressant, was the substitution of ________ for less environmentally-friendly solvents.
- Esters are often used as
- Many of the flavors isolated from foods are
- Vinegar is a solution of ________ in water.
- The general formula for a carboxylic acid is
- The -COOH group represents the
- Aldehydes and ketones share a common functional group. The group is the
- The abbreviation ROR' is used to represent the general formula of a(n)
- Compounds that have two alkyl groups attached to an oxygen atom are called
- Phenol, sometimes called carbolic acid, was the first
- A phenol has a(n) ________ group attached to a benzene ring.
- Phenols are often used as
- Compounds with a hydroxyl group attached directly to a benzene ring are called
- A homologous series of alcohols contains