1. Reaction of Iron and Steam

The reaction between iron and steam involves the formation of iron(II) oxide and hydrogen gas. This reaction can be represented by the following equation:

Fe(s) + H2O(g) → FeO(s) + H2(g)

In this equation, Fe represents iron, H2O represents steam, FeO represents iron(II) oxide, and H2 represents hydrogen gas. The reaction occurs at high temperatures and is commonly known as the steam-iron reaction.

When steam comes into contact with iron, it reacts with the iron to form iron(II) oxide and hydrogen gas. The iron(II) oxide is a black solid, while the hydrogen gas is a colorless and odorless gas. This reaction is an example of a redox reaction, where iron is oxidized and steam is reduced.

This reaction is often used in industrial applications, such as in the production of hydrogen gas. Iron is also commonly used as a catalyst in the Haber process, which is used to produce ammonia.

2. Reaction of Calcium and Potassium with Water

The reaction between calcium and water and the reaction between potassium and water are similar in nature. Both reactions involve the formation of metal hydroxides and hydrogen gas. The equations for these reactions are as follows:

Ca(s) + 2H2O(l) → Ca(OH)2(aq) + H2(g)
2K(s) + 2H2O(l) → 2KOH(aq) + H2(g)

In these equations, Ca represents calcium, H2O represents water, Ca(OH)2 represents calcium hydroxide, K represents potassium, and KOH represents potassium hydroxide.

When calcium or potassium reacts with water, they undergo a displacement reaction. The metal displaces hydrogen from water, forming metal hydroxides and releasing hydrogen gas. Calcium hydroxide and potassium hydroxide are both strong bases and are soluble in water.

The reaction between calcium and water is less vigorous compared to the reaction between potassium and water. Calcium reacts slowly with water, while potassium reacts more vigorously, often producing flames and sparks.

3. Reaction of Potassium with Water

The reaction between potassium and water is highly exothermic and violent. It is an example of a highly reactive metal reacting with water. The equation for this reaction is as follows:

2K(s) + 2H2O(l) → 2KOH(aq) + H2(g)

In this equation, K represents potassium, H2O represents water, KOH represents potassium hydroxide, and H2 represents hydrogen gas.

When potassium reacts with water, it undergoes a displacement reaction, where the metal displaces hydrogen from water. The reaction is highly exothermic, releasing a large amount of heat. It is also accompanied by the evolution of hydrogen gas.

The reaction between potassium and water is highly vigorous and often produces flames and sparks. It is important to handle potassium with extreme caution due to its reactivity with water and air. Potassium hydroxide, the product of the reaction, is a strong base and is soluble in water.