Preparation of a- and p-Stannic Acid

Preparation of -Stannic Acid. Treat 0.5 g of tin with a 40-50 % nitric acid solution with heating. What do you observe Thoroughly wash the precipitate with water by decantation. See how P-stannic acid reacts with alkalies and acids. Compare the chemical activity of cs- and P-stannic acids. 

Preparation of Tin(n) Chloride. Put 2 g of tin into a porcelain bowl and treat it while heating with 20 ml of a 24% hydrochloric acid solution. Put small pieces of platinum into the bowl. Why does the tin dissolve more rapidly in the presence of platinum  

Evaporate the solution up to the beginning of crystallization. Filter off the crystals. What is their composition Write the equation of the reaction. Study the properties of tin(II) chloride. 

Preparation of Tin(IV) Chloride. Assemble an apparatus as shown in Fig. 139 and thoroughly dry it (for what purpose ). Put 

4-5 g of metallic tin or 6-8 g of anhydrous tin(II) chloride into 25-ml Wurtz flask 1. Pass a stream of dry chlorine through the apparatus. When flask 1 becomes filled with chlorine, slightly heat it. What do you observe Continue heating if the reaction stops. What is the colour of tin (IV) chloride due to How can it be purified  

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