Identifying Unknown Using Stoichiometry Lab

Identifying unknown using stoichiometry Experiment 2 Experiment performed on 2/22/2021 Hypothesis: The only difference between sodium carbonate and sodium bicarbonate is the amount of CO2 produced during the reaction. Since the CO2 production is the only component of the reaction that would cause a significant change in pressure, the pressure measurements of the reactions of both unknown chemicals with HCl can provide a direct link to the stoichiometry of CO2. Chemicals and hazard: Chemical name Sodium chloride Sodium carbonate Hydrochloric acid water Carbon dioxide Sodium hydrogen carbonate Molecular formula NaCl Na2CO3 HCl H2O CO2 NaHCO3 Molar mass Amount used 58.44 g/mL 105.989 g/mL 36.458 g/mL 18.01528 g/mL 44.01 g/mL 88.007 g/mL ‘product’ 25 mL 50 mL ‘product’ ‘product’ 25 mL Lab safety: Hazards of sodium chloride: Inhalation: May cause mild irritation to the respiratory tract. Ingestion: Very large doses can cause vomiting, diarrhea, and prostration. Dehydration and congestion occur in most internal organs. Hypertonic salt solutions can produce violent inflammatory reactions in the gastrointestinal tract. Skin Contact: May irritate damaged skin; absorption can occur with effects similar to those via ingestion. Eye Contact: Causes irritation, redness, and pain. (For salt concentrations greater than the normal saline present.) Managing Exposure to sodium chloride: Inhalation: Remove to fresh air. Get medical attention for any breathing difficulty. Ingestion: If large amounts were swallowed, give water to drink and get medical advice. Skin Contact: Wash exposed area with soap and water. Get medical advice if irritation develops. Eye Contact: Immediately flush eyes with plenty of water for at least 15 minutes, lifting upper and lower eyelids occasionally. Get medical attention if irritation persists. Hazards of sodium hydrogen carbonate: Respiratory If sodium bicarbonate dust in the worker’s breathing zone can’t be controlled with ventilation or other engineering means, workers should wear respirators or dust masks approved by a certification organization, such as The National Institute for Occupational Safety and Health (NIOSH), for protection against this chemical. Skin Protective gloves and clothing should be worn. Eyes Since sodium bicarbonate is most-often seen in a powder-like state, chemical safety goggles should be worn and an area to wash eyes and skin should be located in the work area. If this chemical gets into a worker’s eyes, it can cause mild to moderate irritation. Managing Exposure to Sodium Bicarbonate: Even though sodium bicarbonate is relatively safe compared to other chemicals in the workplace, as with any chemical, all unnecessary exposure should be avoided. In the event exposure occurs, the following steps should be taken: 1) Eye Contact Flush eyes with plenty of water and seek medical attention if irritation occurs. 2) Skin Contact Wash skin with plenty of soap and water and seek medical attention if irritation occurs. 3) Inhalation Individual should be removed from exposure and immediately moved to an area with fresh air. Seek medical attention immediately if any breathing difficulty occurs. 4) Ingestion Drink plenty of water and seek medical attention if discomfort persists Handling Sodium Bicarbonate Spills: If sodium bicarbonate spills, it can be recovered and re-used if contamination hasn’t occurred. Vacuuming or wet sweeping are recommended to avoid dispersing dust. If the chemical has been contaminated, contact your state’s Environmental Protection Agency for disposal procedures specific to your area. Proper Sodium Bicarbonate Storage Sodium bicarbonate should be stored in a tightly closed container and placed in a cool, dry, well-ventilated area. Keep away from acids, excessive heat and moisture. Hazards of Sodium carbonate:  Inhalation - Seek fresh air. If victim’s breathing is difficult, administer oxygen. If breathing is absent, give artificial respiration and seek medical attention immediately.  Eye Contact - Check for and remove contact lenses. Immediately flush eyes with plenty of water for at least 15 minutes. Seek medical attention.  Skin Contact - Flush skin with plenty of water and cover any irritated skin with an emollient. Remove contaminated clothing. Get medical attention.  Ingestion - Do NOT induce vomiting. Loosen tight clothing. Never give anything by mouth to an unconscious person. Seek immediate medical attention. Storing & Disposing of Sodium Carbonate Keep sodium carbonate in a cool, well-ventilated area away from any sources of moisture. Keep any container with this chemical tightly closed. Do not store above 24°C (75.2°F). This chemical must be disposed of in accordance with federal, state, and local environmental control regulations. Hazards of hydrochloric acid: Skin Contact – If hydrochloric acid comes into contact with your skin, flush immediately with plenty of water for at least 15 minutes, and remove any contaminated clothing. In case of serious skin contact, use water, a disinfectant soap, and anti-bacterial cream. Seek immediate medical attention. Eye Contact – If hydrochloric acid or acidic mists get into your eyes, immediately flush with plenty of water for at least 15 minutes. Seek immediate medical attention. Ingestion – If swallowed, do not induce vomiting. Seek immediate medical attention. Inhalation – If you inhale hydrochloric acid vapors or mists, seek fresh air and medical attention immediately. Hydrochloric Acid Storage and Disposal Hydrochloric acid should be stored in a cool, dry, well-ventilated area away from sources of moisture. Keep away from incompatible materials such as oxidizing agents, organic materials, metals and alkalis. Hydrochloric acid has the ability to corrode metallic surfaces. Keep container tightly closed and store in a safe place. Hazards of water: No serious hazards. Hazards of carbon dioxide: Inhalation: Take In case of oxygen deficiency: take precautions to ensure your own safety before attempting rescue (e.g. wear appropriate protective equipment). If breathing is difficult, trained personnel should administer emergency oxygen. If the heart has stopped, trained personnel should start cardiopulmonary resuscitation (CPR) or automated external defibrillation (AED). Immediately call a Poison Centre or doctor. Treatment is urgently required. Transport to a hospital. Skin Contact: Not applicable (gas). Liquefied gas: quickly remove victim from source of contamination. DO NOT attempt to rewarm the affected area on site. DO NOT rub area or apply direct heat. Gently remove clothing or jewelry that may restrict circulation. Carefully cut around clothing that sticks to the skin and remove the rest of the garment. Loosely cover the affected area with a sterile dressing. DO NOT allow victim to drink alcohol or smoke. Immediately call a Poison Centre or doctor. Treatment is urgently required. Transport to a hospital. Eye Contact: Not applicable (gas). Liquefied gas: immediately and briefly flush with lukewarm, gently flowing water. DO NOT attempt to rewarm. Cover both eyes with a sterile dressing. DO NOT allow victim to drink alcohol or smoke. Immediately call a Poison Centre or doctor. Treatment is urgently required. Transport to a hospital. Ingestion: Not applicable (gas). General precaution and protection: Wear safety goggles, and gloves always while in the lab and stick to the dress code of the lab. Materials used for the experiment:       Erlenmeyer flask 3 syringes Vernier gas pressure sensor Lab quest Laptop Beaker Procedure: 1. Wear safety goggles, gloves and make sure to have your mask on 2. Label your chemicals 3. Get 125 mL Erlenmeyer flask 4. On the ring stand connect the tube that is connected to the neck of the 125 mL Erlenmeyer flask 5. Connect the tube to the gas pressure sensor and put it in the Erlenmeyer flask 6. Gas sensor must be at channel 1(connect gas pressure sensor to lab quest) 7. Connect the lab quest to your laptop 8. Connect the USB to the laptop 9. Open the LoggerPro software on your laptop 10. Click on experiment ‘change unit’ 11. Click on lab quest 2 and select atm 12. Pick some base using a beaker 13. Fill 1 mL of NaHCO3 into your syringe 14. Screw it at the cork and insert the 5mL of base into the Erlenmeyer flask 15. Turn the stop cork to stop the flow into the Erlenmeyer flask 16. Record the value of pressure 17. Do the same steps (11,12,13 and 14) but with 2 mL of base 18. Keep repeating the same steps with 3mL 4 and 5mL of base 19. Record the value of pressure after pouring each amount into the flask 20. Pick some acid using a beaker 21. Fill 5 mL of HCl into your syringe 22. Screw it at the cork and insert the 5mL of acid into the Erlenmeyer flask that has the base in it. 23. Turn the stop cork to stop the flow into the Erlenmeyer flask 24. Record the value of pressure 25. Do the same steps (19,20,21 and 22) but with 4 mL of acid 26. Keep repeating the same steps with 3mL 2 and 1mL of acid 27. Record the value of pressure after pouring each amount into the flask 28. Swirl the flask a little bit so the acid and base solution mix well together 29. Wait for the logger pro curve to become a straight line 30. Click stop, then record the data 31. Subtract the initial value of pressure from the final one to obtain the change in pressure 32. Clean everything on the table using a wet napkin 33. Spill the acid and base into the chemicals container (only water goes into the sink) Note: if you spill acid, add base to it to neutralize it and vice versa.