The stationary phase of the GC columns in the organic chemistry labs is silicone oil, and so the boiling points of the sample compounds determine the order of elution. The highest boiling species is the last to elute from the column. In the analysis of your distillation fractions by GC, the peak that elutes first from the column will correspond to which component of the mixture?

In a laboratory experiment, a fermenting aqueous solution of glucose and yeast produces carbon dioxide gas and ethanol. the solution was heated by burning natural gas in a bunsen burner to distill the ethanol that formed in the flask. during the distillation, the ethanol evaporated and then condensed in the receiving flask. the flame of the burner was kept too close to the bottom of the flask and some of the glucose decomposed into a black carbon deposit on the inside of the flask. during this experiment the following changes occurred. which of these changes involved a physical change and not a chemical change? check all that apply. 1-condensation of ethanol 2-evaporation of ethanol 3- formation of carbon dioxide gas from glucose burning of natural gas 4-formation of ethanol from glucose by yeast 5-formation of a carbon deposit inside the flask

Write a paragraph that provides examples of each stage of volcanic activity, a description of the volcano, and facts about each stage.

For each of the following types of reactions, write a general reaction formula in the symbolic form—for example, a + b → ab. single-displacement double-displacement synthesis decomposition