1. Reaction Rates

2. Purpose
To compare the rate of reaction with the varying concentration of a reactant

3. Procedure
Obtain one 10 mL and one 50 mL graduated cylinder and a beaker. All chemicals will be at your lab station
You will be diluting Solution A (Na2S2O3). For trial one, put 10 mL of Solution A into one graduated cylinder and add 40 mL of water.
Put 5 mL of HCl into graduated cylinder
Put an “X” on a piece of paper. Pour the solutions into the beaker and record the time it takes to change color and not see the “X”. Dump down sink and rinse flask.

4. Procedure
For trial two, mix 20 mL of solution A into the graduated cylinder and 30 mL of water.
Always put 5 mL of solution B into the other graduated cylinder.
Mix the two solutions in the beaker and record the time to not see the “X”. Dump down sink and rinse.
Repeat with other 3 trials.

5. Data
Na2S2O3
Water
HCl
Time
10 mL
40 mL
5 mL
20 mL
30 mL
50 mL
0 mL

6. Graph

7. Conclusion
In this lab, we reacted a sodium thiosulfate solution with hydrochloric acid to produce sulfur (solid). We varied the concentration of the sodium thiosulfate solution. As the concentration decreased, the rate of the reaction _____________. (2 more sentences)