Assume you added 1.0 M hydrochloric acid rather than 1.4 M hydrochloric acid to
ID: 806331 • Letter: A
Question
Assume you added 1.0 M hydrochloric acid rather than 1.4 M hydrochloric acid to the reaction mixture. How might this affect your results?
A)an acid environment is required to dissolve basic magnesium salts and then for the water to react to form triphenylmethanol, if the solution is not acidic enough , the yield is reduced.
b)The hydrochloric acid is added to slow the reaction rate so a less concentrated acid will allow increased reaction rate and increased yield
c) Since the hydrochloric acid is the solvent, the reaction may occur more slowly but have no effect on yield
d) the hydrochloric acid is used to dissolve any remaining magnesium which is filtered out later anyway, so it would have no effect on the results
How many mL of bromobenzene are required to produce 8.25 g of triphenylmethanol?
Calculate the theoretical yield of triphenylmethanol beginning with 7.27 g of benzophenone.
Explanation / Answer
1.The hydrochloric acid is added to slow the reaction rate so a less concentrated acid will allow increased reaction rate and increased yield
2.
Assume that you prepared phenylmagnesium bromide by reacting 2.1 mL of bromobenzene (density 1.50 g/mL) with 0.50 g of magnesium in anhydrous ether. To this, you slowly added a solution of 2.4 g benzophenone in anhydrous ether. You obtained 2.6 g of triphenylmethanol. What was your percent yield?
The equations are (Ph = C?H?):
PhBr + Mg ? PhMgBr
Ph?C=O + PhMgBr ? Ph?COMg Br
Ph?COMg Br + H? ? Ph?COH + Mg