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complete combustion of pentane and Graham's law of diffusion

3. Consider the hydrocarbon pentane, C5H12 (molar mass 72.15 g).

(a) Write the balanced equation for the combustion of pentane to yield carbon dioxide and water.

(b) What volume of dry carbon dioxide, measured at 25 C and 785 mm Hg, will result from the complete combustion of 2.50 g of pentane?

(c) The complete combustion of 5.00 g of pentane released 243 kJ of heat. On the basis of this information calculate the value a deltaH for the complete combustion of one mole of pentane.

(d) Under identical conditions, a sample of an unknown gas effuses into a vacuum at twice the rate that a sample of pentene gas effuses. Calculate the molar m ass of the unknown gas.

(e) The structural formula of one isomer of pentane is shown below. Draw the structural formulas for the other two isomers of pentane. Be sure to include all atoms of hydrogen and carbon in your structures.

Solution Summary

The first part of the solution concentrates on the complete combustion of pentane calculation, such as the enthalpy. The second part of the solution is an application of Graham's law of diffusion to find out the molar mass of the gas. It also explains the structural formula of isomers of pentane