Chemistry – Chemical reactions - Rate of reaction | e-Consult
Chemical reactions - Rate of reaction (1 questions)
Method: The experiment involves reacting a fixed mass of iron with hydrochloric acid of varying concentrations. The time taken for the reaction to produce a measurable volume of hydrogen gas is measured for each concentration. The volume of hydrogen gas produced can be measured by collecting it over water in an inverted test tube.
Variables and Expected Observations:
| Concentration of HCl (mol/dm3) | Time taken for reaction to produce 25 cm3 of H2 (s) | |
| 0.1 | ? | ? |
| 0.2 | ? | ? |
| 0.3 | ? | ? |
| 0.4 | ? | ? |
Analysis of Results: The rate of reaction can be calculated as the reciprocal of the time taken (rate = 1/time). A graph of rate of reaction (1/time) against the concentration of HCl would be plotted. If the rate of reaction is directly proportional to the concentration of HCl, the graph will be a straight line passing through the origin. This would indicate a first-order reaction with respect to HCl. The slope of the line would be equal to the rate constant (k) for the reaction.