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Rate of Reaction - Clock Lab
Chemical Reactions
Effect of concentration on rate of reaction:
Directions(Procedures)
1. Add the appropriate amount of Solution A (see table below for volumes) and amount of water to the 100ml beaker.
2. Pour out the appropriate amount of Solution B into 25ml graduated cylinder.DO NOT ADD TO 100ml BEAKER UNTIL HAVE STOPWATCH
3. Add all Solution B into 100ml beaker at once, start stopwatch and swirl solutions until "solution turns blue".
4. Record time.
5. Dispose of solution into sink and clean 100ml beaker. Use only one graduate cylinder for each solution for all trials
| Data Table: Volumes of Solutions vs. Reaction Rate |
| Trial # |
Solution A |
Water |
Solution B |
Rate of Rxn(sec)
|
| Trial 1 |
10.ml |
0ml |
10.ml |
______________ |
| Trial 2 |
7.5ml |
2.5ml |
10.ml |
______________ |
| Trial 3 |
5.0ml |
5.0ml |
10.ml |
______________ |
Questions
1. What is causing the blue color in the solution?
2. In general, as you decrease the concentration of Solution A, what happens to the time to see the blue color? Why (remember the two words you need to use in explanation)