Why does dilute acid react with metal

Understand chemistry 4, textbook

40 3  Workbook page 25 40.1 Aluminum chloride (Al 3+ Cl - 3) is often a component of deodorants and reduces sweating. Salts of acids 1. How and from what are salts formed? What is the metal doing in the acid? (Fig. 40.2) Place three snap-cap jars with dilute hydrochloric acid next to each other. Put a piece of magnesium in the first glass, a piece of zinc in the second glass, and a small piece of copper in the third glass. What reaction can you observe in each case? What is the result? At V1, gas bubbles rise in the first and second snap-cap jars. Gaseous hydrogen is produced. The metals have not disappeared. With the acid you have formed the dissolved salts magnesium chloride and zinc chloride. Nothing happens in the third glass. Copper does not react with hydrochloric acid. When a base metal dissolves in an acidic solution, a salt-like substance forms in addition to the hydrogen gas. We call this substance the acid salt. Metal + Hydrochloric Acid  Metal Chloride + Hydrogen Magnesium + Hydrochloric Acid  Magnesium Chloride + Hydrogen Mg + 2 HCl  Mg 2+ Cl - 2 + H 2 The blue salt (Fig. 40.3) - LV in the fume cupboard In a snap-lid glass that is half filled with concentrated nitric acid is filled, a laboratory spoon of copper (III) oxide is dissolved. Then it is diluted with water. Then some liquid is poured into a porcelain bowl and evaporated over the burner. What is forming? At V2 a green solution and brown gases (nitrogen dioxide, NO 2) are formed. When diluted with water, the solution turns bluish in color. After evaporation, a bluish salt (copper nitrate) has formed. If metal oxides dissolve in acids, salts are also formed. In biological wastewater treatment plants, iron chloride (Fe 3+ Cl - 3), for example, is used to precipitate phosphates and remove solids (flocculation and sinking). M Salts are formed when metals or metal oxides are dissolved in acids. Salts consist of positive metal ions (eg Na +, Ca 2+) and negative acid residue ions (eg Cl -, SO 4 2–). The ions attract each other and form regular crystal lattices. V1 V2 40.2 What is the metal doing in the acid? 40.4 Iron (II) chloride (solution and pieces) 40.5 Copper sulfate (Cu 2+ SO 4 2–), the copper salt of sulfuric acid 40.6 Crystal lattice model of table salt (Na + Cl -) 40.3 The blue salt worksheets fy67ff For testing purposes only - property of Verlag öbv

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