Pentane, isomers

Determine the equilibrium distribution of the three pentane isomers given the following data on free energies of formation at 600 K. Assume ideal gas behavior. 

These are derived by first writing the carbon skeletons of all pentane isomers and then introducing one double bond. A double bond can be placed in n-pentane in two ways to give two isomers. 

A-8. Write a balanced chemical equation for the reaction of chlorine with the pentane isomer that gives only one product on monochlorination. 

The dependence of the rate constant, K, in Equation 2 on temperature (Figure 6) show tl jgg argj ac v t g r gy in n-pentane isom-... 

For butane and hexane, the experimental equilibria agree fairly well with equilibria calculated from thermodynamic data (22). However, the pentane isomer favored thermodynamically, neopentane (2,2-dimethyl-propane), is not obtained, possibly because of steric hindrance or the instability of ions intermediate in the reaction mechanism. 

Pentane isomers, C5H12, have boiling points in the range of normal ambient conditions, and represent the approximate borderline between gases and liquids in the paraffin series (Eq. 18.3). 

Figure 12 The three pentane isomers obtained with McKay s orderly algorithm and the -tuple code. Hydrogen atoms are not represented. All atoms are carbons and can have up to four bonds. Parent-child and child-parent relationships are indicated with arrows. Canonical w-tuples are written in parentheses. At each layer, a bond and a new atom are added. The added atom is represented by a solid node. The last bond/atom in the canonical -tuple is represented by a dashed line and is underlined in the canonical n-tuple. A graph is rejected when its legitimate parent is not the graph it came from. This case develops when the added bond/atom is not the last digit of the canonical -tuple (the dashed line is not linked to the solid node).

Fig. 13.4. Pentane isomer groups are arranged differently, but the formula is the same.

KOS Kostko, A.F., Lee, S.H., Liu, J., DiNoia, T.P., Kim, Y., and McHugh, M.A., Cloud-point behavior of poly(ethylene-co-20.2 mol% 1-butene) (PEBIO) in ethane and deuterated ethane and of deuterated PEBIO in pentane isomers, J. Chem. Eng. Data,... 

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