Determining the Rate of Reaction When Reacting Magnesium Powder with Hydrochloric Acid Essay

AimTo determine the calculate of reception forResearch QuestionWhat force does the submerging of hydrochloric acid have on the invest of chemical reply when combined with magnesium powder?HypothesisI hypothesise that the volume of enthalpy suck produced bequeath increase at a steep, but steady rate as the concentration of hydrochloric acid increases, until the concentration is equal to 1.0 mole dm-3. in that locationfore, the rate of reaction will remain constant until this point. I suggest this concentration because the standard concentration of hydrochloric acid used in general experiments is usually 1 mol dm-3. I then theorize that the rate of reaction will gradually decrease until the gradient of the graph (effect of increasing concentration of HCl against the volume of hydrogen produced line graph 1) becomes 0.VariablesType of VariableVariableEnsured byDependent Variable* Time Taken* Timed using stop clock* heap of Hydrogen Gas Produced* Experiment repeated three tim e & Average takenIndependent Variable (quantitative)* Concentration of HCl(aq)* 8 concentrations were usedControlled Variables* Temperature* Water bathroom was used* Thermometer placed in water bath* Mass of Magnesium* employ a 3 d.p. balance* Surface Area of Magnesium* Used powder & made sure hand was the same* Volume of Hydrochloric Acid* A burette was used to measure volumeRequirements* water bath (30oC)* 500cm3 conelike flask* rubber stopper* delivery tubing* measuring cylinder* clamp stand* stop clock* 0.06g magnesium powder* 20cm3 hydrochloric acid* 3 d.p. balance* spatula* weighing boat* burette (x2)* thermometer in water trough* safety gogglesApparatusTechnical Notes1) The magnesium powder should be as pure as possible. It should be stored in a clean and dry environment to ensure that no impurities (such as cause of oxidation) prevent the collection of finished data.2) Eye protection is necessary due to the use of hydrochloric acid tiny bubbles may cause irritation of eyes.3) Rubber, instead of cork, must be used as the material for the bungs. Cork is too porous and will leak.4) No naked flames should be present hydrogen gas is extremely flammableMethod1. The solutions were alert with a calculated combination of hydrochloric acid and water, to produce 8 different concentrations of 20cm3 hydrochloric acid2. The apparatus was set up as shown in the diagram. The trough was fractional filled with water3. The measuring cylinder was filled with water, and remained full whilst being turned upside-down (as in diagram)4. The magnesium powder was added to the conical flask rapidly and the bung was replaced as fast as possible to prevent any gas escaping. The stop clock was started.5. The volume of the gas was then collected in the measuring cylinder, measured and recorded after 30 seconds6. Steps 3-5 was repeated three times with fresh materials, and an average volume of gas collated was calculated for that concentration7. This process (steps 1-6) was repeated for the 7 other concentrations (0.25 2.00M)8. The rate of reaction was then calculated for each of the concentrationsObservations* As the magnesium powder reacted with the hydrochloric acid, fizzing on the come along was evidence of a reaction taking place.ConclusionFrom my data and calculations, I determined the rate of reaction (for concentration of HCl 0.25 to 2.00M) to be between 0.24 and 1.14 (respectively) 11.68%.The rate of reaction is affected by a number of factors. Increasing the concentration of reactants will usually cause the rate of reaction increase. A higher concentration will mean that there is more of the reactant to collide together and react.By measuring the volume of gas (hydrogen) evolved at each concentration, I was able to calculate the rate of reaction for each of the concentrations.The volume of gas evolved increases as the concentration of HCl (aq) increase, as does the rate of reaction (the gradient of line graph 1). However, the graph showin g the rate of concentration against average volume of gas (i.e. showing the rate of reaction) begins to level off at 1.25M, and not 1.00M, as I hypothesised.This could be associated to one or many of the random or systematic errors, resulting in 11.68% uncertainty for the value of rate of reaction. It could also be that my hypothesis was proved wrong on this account.There is no standard rate of reaction, as it is different for each trial, since the rate of reaction is dependent on concentration. There is not single rate of reaction for this type of experiment.EvaluationVariablePossible ProblemsPreventionTemperature of Hydrochloric AcidIf the temperature increases, it could be the cause of any change in rate of reaction & would mask the effects of the change in concentrationThe flask was placed in a water bath set at 30oC in order to keep it at a constant temperature & eliminate this as an independent variableVolume of Hydrochloric AcidIf the volume varies, it could be responsible fo r an increase or decrease in the rate of reaction & it would not be a reliable experiment20cm3 of hydrochloric acid was used for every experimentMass of Magnesium PowderIf the mass increases, it would alter the rate of reaction & would cause inaccurate results0.06g of magnesium powder was used for every experiment