Topic:
Investigation of Action of Saliva and 3 M Hydrochloric Acid In Two Carbohydrate Solution

Objective:
To investigate the action of saliva and 3 M Hydrochloric Acide in two Carbohydrate Solution

Apparatus & Equipment:
Boiling tubes
Beaker
Graduated plastic dropper
Water bath, (~ 37oC)
Water bath, (~ 95oC)

Materials:
Carbohydrate solution A
Carbohydrate solution B
Benedict’s solution
3 M Hydrochloric acid
3 M Sodium hydroxide
Iodine solution

Procedures:
Part 1
1. Two boiling tubes were prepared containing 1 ml solution A and 1 ml solution B respectively. 1 ml Benedict’s solution was added to each tube. Both tubes were heated together in the (~95oC) water bath for two minutes. The results were recorded in table 1.
2. Few drops of solution A and B were added separately on a white tile. On each solution, 1-2 drops of iodine solution were added. The observations were recorded in the table 1.

Part 2
3. The boiling tubes were labelled 1, 2, 3 and 4. 2 ml of solution B were pipette into each of four boiling tubes.
4. Tubes 1 and 2were placed in a water bath of ~37oC to heat up the solution.
5. The saliva was salivated into a small beaker until it reaches approximate 5 ml.
6. This step was done approximately at the same time. 2 ml of saliva prepared were pipette into tubes 1 and 4. The contents of the tubes were shaken well to ensure thorough mixing. 2 ml of HCl were pipette into tubes 2 and 3.
7. Tubes 1, 2, 3 & 4 were incubated at their respective temperatures (see Table 2) for 30 minutes from that moment.
8. 4 more new boiling tubes were labelled as follows: 1’, 2’, 3’ and 4’.
9. After 5 minutes of incubation of tubes 1 to 4, 2 ml of the contents were poured out from all these tubes into the respective newly labelled tubes (e.g., 1 into 1’, 2 into 2’, 3 into 3’ , and 4 into 4’). The original tubes were placed back into the