The Relative Stabilities of Cycloalkanes: Ring Strain

  The Relative Stabilities of Cycloalkanes: Ring Strain ** Cycloalkanes do not all have the same relative stability. Experiments have shown that cyclohexane is the most stable cycloalkane and that, in comparison, cyclopropane and cyclobutane are much less stable. This difference in relative stability is due to ring strain, which comprises …

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Sigma Bonds and Bond Rotation

    Two groups bonded by only a single bond can undergo rotation about that bond with respect to each other: ** The temporary molecular shapes that result from such a rotation are called conformations of the molecule.   ** Each possible structure is called a conformer.   ** An analysis of the …

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pH Scale

  pH Scale ** The concentration of H+ or OH− in aqueous solution can vary over extremely wide ranges, from 1 M or greater to 10−14 M or less. ** To construct a plot of H+ concentration against some variable would be very difficult if the concentration changed from, say, 10−1 M to 10−13 M. This …

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The Zeroth Law of Thermodynamics

  Introduction ** Thermodynamics is based on a few statements called laws that have broad application to physical and chemical systems. ** As simple as these laws are, it took many years of observation and experimentation before they were formulated and recognized as scientific laws.   ** Three such statements …

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System, Surroundings, and State

  What is the System and  Surroundings ? ** Imagine you have a container holding some material of interest to you, as in Figure  blow. ** The container does a good job of separating the material from everything else.   ** Imagine, too, that you want to make measurements of …

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Measuring Mass

  In most analyses, an analytical balance must be used to measure masses with high accuracy. Less accurate laboratory balances are also used for mass measurements when the demands for reliability are not critical. Types of Analytical Balances What is An analytical balance ? ** An analytical balance is an …

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Nomenclature of Cycloalkanes

  What is Cycloalkanes? ** Saturated cyclic hydrocarbons are called cycloalkanes, or alicyclic (aliphatic cyclic) compounds, and have the general formula (CH2)n or CnH2n.  ** Cycloalkanes are named by adding “cyclo” before the parent name of alkane.   ** Substituted cycloalkanes are named by rules similar to those for open chain …

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