haloform

a.If you were carrying out an industrial scale sythesis in which one step involved a haloform reaction to convert a methyl ketone into the corresponding acid having one less carbon atom, would you use NaOH and Cl2, NaOH & Br2, or NaOH and I2 reagent? Give reasons. b. Write a balanced equation for the conversion of C6H5CHOHCH3 to methyl ketone in the presence of I2 and NaOH. Identify which is being oxidized and which is being reduced.

chemical tests

a. What chemical tests might be used to ditinguish between pentanal and 2-pentanone; between benzyl alcohol and diphenylmethanol? b. Pinacol upon heating in aqueous acid, rearranges to form pinacolone. Suggest a mechanism for this reaction.

Dilution

A serial dilution is used to prepare solutions containing amounts(grams)of chemicals so small that they would be impossible to measure with ordinary balance. If 5.00ml of a .10 Molar salt (NaCl) solution is diluted to 500ml,then diluted to 500ml of another new solution, what is its concentration. If 5.00 ml of this solution is diluted to 500ml, what is the concentration of the final solution? How many grams of salt are in the final solution.

solution

A solution of sodium cyanide (NaCN)is prepared by dissolving 50 grams into 500ml of solution. What is the Molarity,%(w/v), andppm of the resulting solution.

Melting Point Determination

1. In a mixture of approx. 20% camphor and 80% naphthalene. What would you expect the melting point to be? (+/-)camphor (175-177 Celsius) and naphthalene (80-81 Celsius). 2. Describe the expected type of error in the observed m.p. (unaffected, high, low and /or broad) when the melting point is determined as follows. a. A Mel-Temp is used and the rate of heating is 15 Celsius/min. b. An excessively large sample size is introduced into the capillary tube before using the Mel-Temp. 3. Decide whether the statement is always true. If not, explain when the statement would not be true. a. An impurity always lowers the melting point of an organic compound. b. A sharp melt... click for more