Nitrate of sodium represents well soluble average salt in water which consists of metal atoms – sodium and the acid rest – nitrate. Other name – sodium saltpeter, nitrate sodium or sodium salt of nitric acid. In a firm look it is colourless crystals which in total give substance of white color. Nitrate sodium can be distinguished by means of high-quality reactions.
It is required to you
- - Sodium nitrate;
- - the concentrated sulfuric acid;
- - copper shavings;
- - torch;
- - test tube or flask;
- - spoon for heating.
Instruction
1. Nitrate of sodium is a complex substance in which solution there are ions of sodium and nitrate ions. Therefore, high-quality reactions have to be carried out consistently on presence of these ions.
2. High-quality reaction to sodium ions. The only way to define sodium is to carry out coloring of a flame. For this purpose light a spirit-lamp, place several kristallik of nitrate of sodium in a special spoon and bring in a flame which will accept coloring of bright yellow color at once.
3. It is possible to alter experience several. For this purpose take paper (it is possible filtering), impregnate it with solution of nitrate of sodium and dry up. For strengthening of further effect it is possible to do these manipulations several times. Then bring paper pieces in a torch flame therefore the flame will also get beautiful yellow coloring. It occurs at the expense of sodium ions.
4. High-quality reaction to nitrate ions. Reagent on nitrate is copper. For this purpose at first or in a flask with nitrate of sodium add the concentrated sulfuric acid to a test tube, and then carefully lower copper shavings or the copper wire cut on pieces. As a result of chemical interaction several products of reaction, one of which is gaseous substance - nitrogen oxide (IV), are formed at once. Otherwise it is called brown gas or "a fox tail" (received such name for coloring). Emergence of brown gas just demonstrates presence at solution nitrate ions. Solution will get blue coloring.
5. During experiments surely follow safety regulations as all substances, both reagents, and reaction products, are especially dangerous. Brown gas is excessively poisonous connection which can cause poisoning, and therefore experiment needs to be made only under draft (in an exhaust case). The concentrated sulfuric acid possesses the water taking away action therefore at hit on skin of hands can cause a severe burn. This reagent also is also dangerous to clothes which need to be protected a dressing gown.