Lab Experiment: Limiting Reactant, Lab Report Example

Introduction

The stoichiometry of the reaction between HCl (hydrochloric acid), H₂SO₄ (sulphuric acid) and NaOH (sodium hydroxide) will be ascertained and the perspective of limiting reactants will be reviewed in this laboratory experiment. The hypothesis that will be tested in this laboratory is that the reagent H₂SO₄administrates the reaction of the chemical process between an acid and a base. This hypothesis is in accordance with the work that was conducted by Sumanasekera, Allen, Fang, Loper, Rao and Eklund (1999).

Background

The idea of limiting reactant is essential in the examination of stoichiometry of reactions between solutes and solvents in chemical reactions. The limiting reactant is the substrate that administrates the amount of recuperation of a solute in a process. This is attributed to the premise that once the limiting reactant has been exhausted; there can be no additional chemical reactions (Sumanaskera et al. 4293).

A method of examining the extent of the chemical reaction in a process is to supervise the thermal energy that is within the reaction systems. Chemicalreactions are usually endothermic of or exothermic as they either absurd energy or liberate thermal energy as they are taking place. The quantity of heat energy that is transmitted is correlated to the amount of precipitate that has formed. The objective of this experiment is to apply a thermometer in order to assess the changes that take place in the temperature as indicators of the extent of the chemical reaction (Sumanaskera et al. 4293).

The stoichiometric reaction will be examined with regards to the manner that H₂SO₄ (sulphuric acid) reacts with NaOH (sodium hydroxide). There will be several trials that are conducted with regards to the chemical reactions between acid and base in order to evaluate the quantities of the reagent that is applied and the variation in the trials. In the examination of the temperature changes occurring while the acid and base are reacting, an index of the extent of the reaction will be derived. . The optimal extent of the reaction will be achieved when the chemical reactants have been combined in the appropriate stoichiometric proportions in order to facilitate the chemical reaction. In the event that the reactants fir a specific trail are not in the appropriate stoichiometric proportions, the reaction  and the temperature changes will be limited during the experiment.

Procedure

There were three separate3.0 M solutions of NaOH, HCl (hydrochloric acid), H₂SO₄ (sulphuric acid).These solutions were diluted to a 1.0 M concentration and mixed in aPlastic Foam Cup. The exothermic qualities of the chemical reactions between NaOH, HCl (hydrochloric acid), H₂SO₄ (sulphuric acid) were evaluated by using a thermometer. The 10 ml graduate, stirring rod and the 600 ml flasks were applied in the laboratory experiment.

Applying the 600ml flasks, measure all of the recommended quantities of 1.0 M HCl and NaOH. The dilution was achieved by adding water.  Use the plastic form cup as a vessel for fascinating the reaction. Measure and pour 45 ml of the 1.0 M HCl. Take the temperature and record it to the nearest ±0.2° C. Next assess, measure and pour 5.0 ml of NaOH into the graduate cylinder. Ensure the simultaneous pouring of the 1.0 M HCl and 1.0 NaOH.

Results and Discussion

On the graphs, the intersecting point of the lines on the graphs is encountered at 0.03 M moles of HCl and 0.04 moles of H₂SO₄. The stoichiometric proportion of NaOH to HCl at the intersecting point of the graph is 1: 1. The balanced chemical equation for the reaction between NaOH and HCl is:

NaOH + HCl ? NaCl + H₂O

The stoichiometry proportion of NaOH and H₂SO₄ at the intersecting point on the graph is 1: 2.  The balanced chemicalequation for the chemical reaction between H₂SO₄ and NaOH is the following:

H₂SO₄ + 2 NaOH ? Na₂SO₄+ H2O

In the event that the experiment would have been conducted with H₃PO₄ and NaOH, the balanced chemical equation would be demonstrated as:

H₃PO₄ + 3NaOH ?Na₃PO₄ + 3 H₂O

The graph of H₃PO₄ and NaOH would demonstrate its point of intersection at 1:3 proportion between H₃PO₄ and NaOH.

Table 1: Point of Intersection on the Graph between the Reagent and Substrate

Error Analysis     

The errors that took place could have been attributed to the measurement of the temperature where there had been a margin for error of ±0.2° C. Additional errors could have been conducted with the transfer of the chemical into the flask. The 600 ml flask had a margin of error of ±0.5 ml. These could have been contributing factors to the error that was manifest between the actual intersection points and the intersection points manifested on the graphs between H₂SO_4, HCl and NaOH.

Conclusion

In this experiment, there had been a hypothesis proposed that the chemical reaction between an acid and a base takes place due to the limiting reactant. In this case, the limiting reactant was the H₂SO₄. The amount and the proportion of H₂SO₄ was the limiting reactant in this experiment. The use of H₂SO₄ as a reagent has been verified. The ratios of the reagent to the substrate were 1: 2. The hypothesis that was proposed was validated by the results of the experiment.

Works Cited

Sumanasekera, GU et al.”Electrochemical oxidation of single wall carbon nanotubes bundles in sulfuric acid.” J. Phys. Chem. B. 103.21(1999):4292- 4297.