Question

question 6
given an unknown solution that contains both starch and glucose,
a. which reagent would you use first to test the solution?
b. which reagent would you use second to test the solution?
a. benedicts...b. sudan iv
iki...b. biuret
a. benedicts...b. iki
a. iki...b. benedicts

Explanation:

Iodine - potassium iodide (IKI) is used to test for starch as it forms a blue - black complex with starch. Benedict's reagent is used to test for reducing sugars like glucose. Since IKI will not interfere with the glucose test and Benedict's reagent may cause color interference with the starch test, we use IKI first to test for starch and then Benedict's to test for glucose.

Answer:

A. IKI
B. Benedict's