A student investigates the reaction between aqueous aluminium chloride and two aqueous solutions of sodium hydroxide, solution $$\(\mathbf{F}\)$$ and solution $$\(\mathbf{G}\)$$. Solution $$\(\mathbf{F}\)$$ and solution $$\(\mathbf{G}\)$$ have different concentrations. The student does three experiments. Experiment 1 - Rinse a burette with distilled water and then with aqueous aluminium chloride. - Rinse a conical flask with distilled water. - Fill the burette with aqueous aluminium chloride. Run some of the aqueous aluminium chloride out of the burette so that the level of the aqueous aluminium chloride is on the burette scale. - Record the initial burette reading. - Use a measuring cylinder to pour $$\(25 \mathrm{~cm}^{3}\)$$ of solution $$\(F\)$$ into the conical flask. - Stand the conical flask on a black or dark-coloured sheet of paper. - Slowly add aqueous aluminium chloride from the burette to the conical flask, while swirling the flask, until the mixture in the conical flask just starts to become cloudy. - Record the final burette reading. Experiment 2 - Refill the burette with aqueous aluminium chloride. Run some of the aqueous aluminium chloride out of the burette so that the level of the aqueous aluminium chloride is on the burette scale. - Record the initial burette reading. - Rinse the conical flask with distilled water. - Rinse the measuring cylinder with distilled water and then with solution $$\(\mathbf{G}\)$$. - Use the measuring cylinder to pour $$\(25 \mathrm{~cm}^{3}\)$$ of solution $$\(\mathbf{G}\)$$ into the conical flask. - $$\(\quad\)$$ Stand the conical flask on a black or dark-coloured sheet of paper. - Slowly add aqueous aluminium chloride from the burette to the conical flask, while swirling the flask, until the mixture in the conical flask just starts to become cloudy. - Record the final burette reading. Experiment 3 - Refill the burette with aqueous aluminium chloride. Run some of the aqueous aluminium chloride out of the burette so that the level of the aqueous aluminium chloride is on the burette scale. - Record the initial burette reading. - Rinse the conical flask with distilled water. - Use the measuring cylinder to pour $$\(25 \mathrm{~cm}^{3}\)$$ of solution $$\(\mathbf{G}\)$$ into the conical flask. - Add 5 drops of thymolphthalein indicator to the conical flask. - $$\(\quad\)$$ Stand the conical flask on a white tile. - Slowly add aqueous aluminium chloride from the burette to the conical flask, while swirling the flask, until the thymolphthalein indicator changes colour. - Record the final burette reading. Compare the concentration of solution $$\(\mathbf{F}\)$$ used in Experiment 1 with the concentration of solution $$\(\mathbf{G}\)$$ used in Experiment 2. Explain your answer. ................................................................................................................................................ . ................................................................................................................................................ . ..........................................................................................................................................

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