To observe and record the different effects of reactants on concentration, surface area, and temperature, on the reaction rates for each. Materials:
Refer to the Experiment 18A worksheet Procedure:
Refer to the Experiment 18A worksheet Data Table:
Mass of 11cm strip of Mg: 0.13g
Average mass of 1 cm piece of Mg: 0.0118 Table 1: Effect of Concentration on Reaction Rate
Concentration of Acid
Reaction Time (s)
Reaction Rate (g Mg/s)
0.5M
480s
2.5 x 10^5 g Mg/s
1.0M
120s
9.8 x 10^5 g Mg/s
3.0M
25s
4.7 x 10^4 g Mg/s
6.0M
11s
1.1 x 10^3 g Mg/s Table 2: Effect of Surface Area on Reaction Rate
Shape of Magnesium Strip
Reaction Time (s)
Reaction Rate (g Mg/s)
Test Tube A sliver
117s
1.0 x 10^4 g Mg/s
Test Tube B rolled
118s
1.0 x 10^4 g Mg/s
Test Tube C flat
101s
1.2 x 10^4 g Mg/s
Table 3: Effect of Temperature on Reaction Rate.
Temperature (°C)
Reaction Time (s)
Reaction Rate (g Mg/s)
Beaker A 1°C
130s
9.1 x 10^5 g Mg/s
Beaker B 32°C
87s
1.4 x 10^4 g Mg/s
Beaker C 50°C
60s
2.0 x 10^4 g Mg/s
Beaker D 98°C
46s
2.6 x 10^4 g Mg/s
Question and Calculations 1.
2 . A. As concentration increases, the reaction rate increases
B. As the surface area increases, the reaction rate remains relatively the same according to my group’s data, but in other circumstances increased surface should increase the reaction rate.
C. As the temperature increases, the reaction rate increases due to higher number of collisions 3. Yes doubling the concentration did double the reaction rate. Because if you look at the datatable above, it took the 6.0M half the time that the 3.0M to dissolve the metal, and this happened because with the higher concentration, you have more collisions, and with more collisions the reaction happens faster. 4. According to my table the flat piece of magnesium dissolved faster than the rest.