Puzzle

5 Greek philosopher who stated matter was continuous, there was no limit on how finely you could cut it up. 

2 Scientist who proposed the model that electrons moving in specific layers. 

6 Greek philosopher who named the smallest partical an atom. 

7 Scientist who proposed that two electrons in the same atom do not have identical sets of all four quantum numbers. 

10 Scientist who first talked about the huge amount of energy of the atom. 

This is the type of hybridization of the carbon atom in the methane molecule. 

This is the tendency of atoms to attract bonding electrons within a molecule. 

This is the attractive force that holds atoms together in a compound. 

The number of electrons necessary to form a double bond. 

This is the combination of pure atomic orbitals to produce new orbitals. 

Solve the clues and place your answers in their correct positions in the grid. 

A reaction where one atom of a molecule is replaced by a different atom. 

It is the abbreviation tor the international union of pure and applied chemistry. 

This synthesis is used while producing alkanes by the reaction of alkyl halides with sodium. 

This homologous series consists of saturated aliphatic hydrocarbons. 

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A further mind-bending collection of puzzles, games and diversions by the undisputed master of recreational mathematics. 

This missing synuuetry provided a great puzzle to theorists in the early part days of quantum mechanics. Taken together, ionization potentials of the first four elements in the periodic table indicate that wavefiinctions which assign two electrons to the same single-particle fiinctions such as... 

The dependence of k on viscosity becomes even more puzzling when the time scale of motion along the reaction coordinate becomes comparable to that of solvent dipole reorientation around the changing charge distribution... 

Analysis of tlie global statistics of protein sequences has recently allowed light to be shed on anotlier puzzle, tliat of tlie origin of extant sequences [170]. One proposition is tliat proteins evolved from random amino acid chains, which predict tliat tlieir length distribution is a combination of the exponentially distributed random variable giving tlie intervals between start and stop codons, and tlie probability tliat a given sequence can fold up to fonii a compact... 

Students are sometimes puzzled at the extraordinarily general application of the process of recrystallisation, since it may appear to them to depend on the assumption that the impurities are more soluble than the... 

The case of i-methyl-4-quinolone is puzzling. The large proportion of the 3-nitro isomer formed in the nitration (table 10.3 cf. 4-hydroxyquinoline) might be a result of nitration via the free base but this is not substantiated by the acidity dependence of the rate of nitration or by the Arrhenius parameters. From r-methyl-4-quinolone the total yield of nitro-compounds was not high (table ro.3). 

Two synthetic bridged nitrogen heterocycles are also prepared on a commercial scale. The pentazocine synthesis consists of a reductive alkylation of a pyridinium ring, a remarkable and puzzling addition to the most hindered position, hydrogenation of an enamine, and acid-catalyzed substitution of a phenol derivative. The synthesis is an application of the reactivity rules discussed in the alkaloid section. The same applies for clidinium bromide. 

Nevertheless, the puzzling fact to be explained is that the harder ring nitrogen prefers the softer electrophilic center and that this preference is more pronounced than the one observed for the amino nitrogen. Much remains to be done to explain ambident heterocyclic reactivity it was shown recently by comparison between Photoelectrons Spectroscopy and kinetic data that not only the frontier densities but also the relative symmetries of nucleophilic occupied orbitals and electrophilic unoccupied orbitals must be taken into consideration (308). 

A vexing puzzle m the early days of valence bond theory concerned the fact that methane is CH4 and that the four bonds to carbon are directed toward the corners of a tetrahedron Valence bond theory is based on the overlap of half filled orbitals of the connected atoms but with an electron configuration of s 2s 2p 2py carbon has only two half filled orbitals (Figure 2 8a) How can it have bonds to four hydrogens ... 

A puzzling feature is that obedience to the Gurvitch rule is by no means universal, the (liquid) volume of water at saturation usually being less than that of the other adsorbate. In Fig. 5.14 for example, the volume of water at... 

Normal ions (M+, Fj+,. .., F +) in a spectrum can provide a molecular structure for substance M if the fragments can be theoretically reassembled. The problem is rather like deducing an original jigsaw puzzle by putting the pieces together correctly. For most molecules containing more than a few atoms, this reassembly exercise is difficult and often problematic. 

In chocolate, cocoa butter is the continuous phase. The characteristic meltabiUty of cocoa butter constitutes a puzzle in chemical stmcture and poses difficulty in replacement cocoa butter has a sharp melting point at body temperature. 

Analysis of Data. A veteran practitioner of chemical market research likened this step to the assembly of a jigsaw puzzle. There are many pieces of unequal size and importance that must be put together to make a picture understandable to everyone. Call reports, secondary data inputs, experience, and judgment are the tools used by the market researcher to analyze the data, reach conclusions, make recommendations, and write the report. 

M Gardner. The Second Scientific American Book of Mathematical Puzzles and Diversions. New York Simon and Schuster, 1961. 

The jelly roll barrel is thus conceptually simple, but it can be quite puzzling if it is not considered in this way. Discussion of these structures will be exemplified in this chapter by hemagglutinin and in Chapter 16 by viral coat proteins. 

Fersht, A.R. Characterizing transition states in protein folding an essential step in the puzzle. Curr. Opin. Struct. Biol 5 79-84, 1994. 

Tjian, R., Maniatis, T. Transcriptional activation a complex puzzle with few easy pieces. Cell 77 5-8, 1994. 

Five double-bond equivalents can be recognised from the shift values (four for the benzene ring and one for the carbonyl group). The sixth double-bond equivalent implied by the molecular formula belongs to another ring, so that the following pieces can be drawn for the molecular jigsaw puzzle ... 

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