LASSAIGNE’S TEST Clause Samples

LASSAIGNE’S TEST. Place about 10 mg or one (1) (small) droplet of the unknown (A, B or C) and about 50 mg of freshly cut sodium metal into a glass tube (Note 1). Heat the tube as strongly as possible until the bottom of the tube is glowing red, holding the tube at this heat for about 5 min. For liquid unknown, start with moderate heating to avoid fast evaporation. Quickly plunge the hot tube into an evaporating dish containing distilled water (~ 10 mL) (Note 2) and cover the dish. Boil the solution on a hot plate for a few minutes while gently crushing the residue with a glass rod. Filter and a colorless filtrate should be obtained. If the volume of filtrate is too little, add distilled water to the filtrate. Use the filtrate for the tests below. A colored filtrate indicates incomplete decomposition and the entire fusion procedure will have to be repeated. Notes: 1. Precautions must be taken when handling sodium. Contact with sodium metal might cause ▇▇▇▇▇ on the human skin. When handling sodium metal, avoid all contact with water. 2. Generally, the glass tube will shatter, and any residual sodium will react with water. Cover the dish immediately with wire gauze once the tube is immersed in water to avoid any splatter. First aid measures to treat sodium induced injuries: 1. If splashed unto eyes, immediately flush water at the eye wash station for at least 15 minutes. Eye washing requires assistance to force the eye open, while reflexes try to shut the eye; attempts to do without help will almost certainly lead to loss of eye sight. Immediate action is required; the first five minutes will decide about saving or losing eyesight. 2. Upon skin contact, wash the part with lots of water for as long as possible. In all cases, one must seek medical aid as soon as possible. All accidents and dangerous occurrences must be reported immediately to the lecturer in charge or the demonstrator or the laboratory assistant. Apart from medical emergencies, sodium might also cause fire!