Solutions for Chapter 9: Chemistry: The Central Science 12th Edition

A protein structure in which the protein is coiled in the form of a helix with hydrogen bonds between C “O and N ¬H groups on adjacent turns. (Section 24.7)

An atom or group of atoms bearing a negative charge.

For chair conformations of substituted cyclohexanes, a position that is parallel to a vertical axis passing through the center of the ring.

The light absorbed by a substance (A) equals the product of its extinction coefficient 1e2, the path length through which the light passes (b), and the molar concentration of the substance (c): A = ebc. (Section 14.2)

A tetrahedral atom, most commonly carbon, that is bonded to four different groups; also called a chirality center

During a reaction, the requirement that the phases of the frontier MOs must be aligned.

A phenomenon observed most commonly for nonequivalent protons connected to adjacent carbon atoms in which the multiplicity of each signal is affected by the other.

Any process with a negative DG.

A crystal lattice in which the lattice points are located at the faces and corners of each unit cell. (Section 12.2)

A reaction that has a rate equation in which the sum of all exponents is one.

Two groups connected to the same carbon atom. For example, a geminal dihalide is a compound with two halogens connected to the same carbon atom.

A reaction which involves the addition of a halogen and a hydroxyl group (OH) across an alkene.

The difference in enthalpy between reactants and products. If the enthalpy of products is lower than that of the reactants, heat is released and the reaction is exothermic. If the enthalpy of the products is higher than that of the reactants, energy is absorbed, and the reaction is endothermic

Cleavage of a bond so that one fragment retains both electrons and the other retains none.

Compounds that are similar in structure to CFCs but also possess at least one C!Hbond.

Bonding that results from intermolecular attractions between molecules containing hydrogen bonded to an electronegative element. The most important examples involve OH, NH, and HF. (Section 11.2)

The vectors a, b, and c that define a crystal lattice. The position of any lattice point in a crystal can be represented by summing integer multiples of the lattice vectors. (Section 12.2)

Anything that occupies space and has mass; the physical material of the universe. (Section 1.1)

A common name for a thiol; that is, any compound that contains an -SH (sulfhydryl) group

A measure of the ease of distortion of the distribution of electron density about an atom or group in response to interaction with other molecules or ions. Fluorine which has a high electronegativity and holds its electrons tightly, has a very low polarizability. Iodine, which has a lower electronegativity and holds its electrons less tightly, has a very high polarizability.