PAG 7.2 Questions and Answers | Latest Version | 2024/2025 | Already Passed

PAG 7.2 Questions and Answers | Latest Version | 2024/2025 | Already Passed **How can you differentiate between primary, secondary, and tertiary alcohols?** 1. Use a spotting tile to combine 3 drops of acidified 0.1 mol dm3 potassium dichromate with two drops of each alcohol in separate test tubes. 2. Observe any changes in color. 3. Record your observations over a 5-10 minute period. **What equipment is necessary for conducting this experiment?** - Safety goggles - Various alcohols - Test tubes - Spotting tiles - Dropping pipette - Potassium dichromate (K2Cr2O7) **What color changes should you expect for each type of alcohol?** - Tertiary alcohol: No observable change - Secondary alcohol: Orange to green - Primary alcohol: Orange to green **How do you identify an aldehyde in a laboratory setting?** 1. Add 2 drops of 0.05 mol dm−3 aqueous silver nitrate to a test tube, followed by enough sodium hydroxide solution to form a brown precipitate. 2. Continue adding aqueous ammonia solution until the precipitate dissolves completely, leaving a colorless solution. 3. Introduce the unknown substance and place the test tube into a warm bath (50-60°C) for 5-10 minutes. **List the equipment required for identifying an aldehyde:** - 0.05 mol dm−3 aqueous silver nitrate - 0.4 mol dm−3 sodium hydroxide solution - 1 mol dm−3 aqueous ammonia - Test tube - Safety goggles