Question

S d Practical Section: Water 50ml Burette Rubber Tubing Rubber Bung 5. Stopper the flask. 6. Cap with Sodium Carbonate 2M HCI Beehive Stand 1. Set up the apparatus as shown in the diagram and have it checked by your Demonstrator. Make sure the level of water in the burette is at the 50cm³ mark. 2. Weigh accurately about 0.2g of sodium carbonate into a small cap. 3. Using a graduated cylinder transfer 15cm³ of 2M HCl (dilute) water into the side armed test-tube. 4. Load the sodium carbonate into the side-armed test tube, making sure that the sodium carbonate does not come into contact with the acid. When the system is airtight, lower the cap to allow the sodium carbonate to come into contact with the acid, allowing the gas to be evolved. Shake the test tube gently to ensure all the gas is displaced, however ensuring that none of the solution in the test tube is transferred elsewhere. 7. When the reaction is complete, record the volume of CO₂ produced. Some carbon dioxide will have dissolved in the water in the burette, producing an acid. By writing the balanced equation between carbon dioxide and water, show what this acid formed is. Therefore, the amount of dissolved (lost) CO2 (in moles) can be determined as follows. 8. After the reaction, empty the contents of the burette into the beaker and add 2 drops of phenolphthalein indicator to this solution. 9. Titrate with NaOH (0.1M) dropwise, (using the microburette) until the solution turns pale pink. Record the exact concentration of NaOH from the container. 10. Accurately determine the volume of NaOH (and thus calculate the moles of consumed). The NaOH reacts with, and thus determines, the moles of CO2 that has dissolved in the water. Express this reaction in terms of a balanced equation. (Hint: first consider H₂O + CO₂ reaction) 11. Repeat the experiment three times to obtain consistent results. Calculate the R-value, individually, for each of your 3 experiments, and comment on which experiment worked best (by comparing with literature value for 'R'). outline the purpose of the experiment referring to the ideal gas equation. ​

Answer 1

This appears to be a detailed procedure for an experiment involving the reaction between sodium carbonate and hydrochloric acid to generate carbon dioxide gas. The steps involve measuring the evolved CO2, determining the amount of dissolved CO2, and calculating its moles using titration with NaOH. Finally, you're asked to calculate the R-value and compare it with the literature value.

The purpose of this experiment seems to be to determine the amount of dissolved CO2 in water and its relationship to the ideal gas equation. The steps outline a process to measure the volume of CO2 produced and dissolved, allowing calculation of the R-value, which is the ideal gas constant.

To summarize, the experiment aims to demonstrate the principles of gas stoichiometry and the ideal gas equation using a specific chemical reaction to determine the dissolved CO2 and compare it to theoretical values. The experimental R-values will indicate the accuracy of the measurements and the success of the procedure in capturing the expected outcomes based on the ideal gas law.