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The sodium fusion test, or Lassaigne's test, is used in elemental analysis for the qualitative determination of the presence of foreign elements, namely halogens, nitrogen, and sulfur, in an organic compound. It was developed by J. L. Lassaigne. [1] The test involves heating the sample with sodium metal, "fusing" it with the sample. A variety ...
A solution of 2% sodium carbonate in water (solution B) [4] Separate storage of the aldehyde and base are necessary to prevent aldol polymerisation of the aldehyde. When exposed to an amine, reaction with acetaldehyde produces the enamine , which subsequently reacts with sodium nitroprusside to the imine .
Sodium nitroprusside crystals are also of interest for optical storage. For this application, sodium nitroprusside can be reversibly promoted to a metastable excited state by blue-green light, and de-excited by heat or red light. [55] In physiology research, sodium nitroprusside is frequently used to test endothelium-independent vasodilation.
The reagent used can be any substance that gives S 2− ions in such solutions; most commonly used are hydrogen sulfide (at 0.2-0.3 M), thioacetamide (at 0.3-0.6 M), addition of hydrogen sulfide can often prove to be a lumbersome process and therefore sodium sulfide can also serve the purpose. The test with the sulfide ion must be conducted in ...
The nitroprusside reaction tests for the presence of free thiol groups of cysteine in proteins; ... The sodium fusion test tests for the presence of nitrogen, sulfur, ...
[7] [8] [6] Sodium is a common component or contaminant in many samples, [2] and its spectrum tends to dominate many flame tests others. [5] The test flame is often viewed through cobalt blue glass to filter out the yellow of sodium and allow for easier viewing of other metal ions. [citation needed]
The nitroprusside anion, [Fe(CN) 5 NO] 2−, a mixed nitrosyl cyano complex, has pharmaceutical applications as a slow release agent for NO. The signalling function of NO is effected via its complexation to haem proteins, where it binds in the bent geometry. Nitric oxide also attacks iron-sulfur proteins giving dinitrosyl iron complexes.
Hot concentrated sulfuric acid oxidizes carbon (as bituminous coal) and sulfur (see sulfuric acid's reactions with carbon): C + 2 H 2 SO 4 → CO 2 + 2 SO 2 + 2 H 2 O S + 2 H 2 SO 4 → 3 SO 2 + 2 H 2 O. Catalysts like selenium, Hg 2 SO 4 or CuSO 4 are often added to make the digestion go faster. Na 2 SO 4 or K 2 SO 4 is also added to increase ...