Question

Sucrose is readily hydrolyzed i.e. broken down back to glucose and fructose by reaction with acidic solution. The hydrolysis can be monitored by measuring the angle of rotation of plane-polarized light passing through the solution because the concentration of sucrose can be inferred from this angle. An experiment on the hydrolysis of sucrose in 0.5 M HCl(aq) produced the following data:

Assume that the reaction is first-order in sucrose, and determine the rate constant k of the reaction and the half-life of sucrose. (4 marks)

t/min	0	14	39	60	80	110	140	170	210
[sucrose]/M	0.316	0.300	0.274	0.256	0.238	0.211	0.190	0.170	0.146

d. The rate law for the hydrolysis of sucrose is found to be rate = k[H+ ][sucrose]. The + initial rate of sucrose hydrolysis is measured in a solution that is 0.01M H+ , 1.0M sucrose, 0.1M fructose, and 0.1M glucose. How does the rate change if

i. [sucrose] is changed to 2.5M (show work)? (2 marks)

ii. [sucrose], [fructose], and [glucose] are all changed to 0.5M (show work)? (2 marks)

iii. [H+ ] is changed to 0.0001M (show work)? (2 marks)

iv. [sucrose] and [H+ ] are both changed to 0.1M (show work)? (2 marks)