Question

Гидроксид металла и водород образуются при взаимодействии с водой а)Feб)Naв)Agг)Caд)Sn

Answer 1

Гидроксид металла и водород образуются при взаимодействии с водой 
Ca+2H2O=Ca(OH)2+H2
2Na+2H2O=2NaOH+H2

Answer 2

Formation of Metal Hydroxide and Hydrogen

When a metal reacts with water, it can form a metal hydroxide and release hydrogen gas. The specific metal that forms a hydroxide and hydrogen when reacting with water can be determined by its reactivity. Let's explore the reactivity of the given metals to identify which one forms a metal hydroxide and hydrogen when reacting with water.

Reactivity of Metals with Water:

- Sodium (Na): Sodium is a highly reactive metal and reacts vigorously with water, forming sodium hydroxide and releasing hydrogen gas.

- Calcium (Ca): Calcium is also a reactive metal and reacts with water to form calcium hydroxide and release hydrogen gas.

- Silver (Ag): Silver is a noble metal and does not react with water under normal conditions. Therefore, it does not form a metal hydroxide or release hydrogen gas when in contact with water.

- Iron (Fe): Iron is less reactive than sodium and calcium. It does not react with water at room temperature. Therefore, it does not form a metal hydroxide or release hydrogen gas when in contact with water.

- Tin (Sn): Tin is also less reactive and does not react with water at room temperature. Therefore, it does not form a metal hydroxide or release hydrogen gas when in contact with water.

Conclusion:

Based on the reactivity of the given metals with water, sodium (Na) and calcium (Ca) are the metals that form metal hydroxides and release hydrogen gas when they react with water. Therefore, the correct answer to the question is b) Na and c) Ca.