Give two reasons to justify

(a) Water at room temperature is a liquid

(b) An iron almirah is a solid at room temperature

To understand why water is a liquid at room temperature while an iron almirah is a solid, we need to consider the properties of matter and how temperature affects different substances. Let's break it down into two parts.

Why Water is a Liquid at Room Temperature

First, let's look at water. The state of a substance—whether it is a solid, liquid, or gas—depends on the arrangement and movement of its molecules. Here are two key reasons why water remains a liquid at room temperature:

• Molecular Structure and Hydrogen Bonding: Water molecules are polar, meaning they have a positive and a negative end. This polarity allows them to form hydrogen bonds with each other. At room temperature, these hydrogen bonds are strong enough to keep the molecules close together, allowing water to maintain a liquid state. If the temperature were to drop significantly, these bonds would become stronger, turning water into ice, a solid.
• Temperature and Kinetic Energy: At room temperature, the kinetic energy of water molecules is sufficient to overcome some of the attractive forces between them. This energy allows the molecules to move freely past one another, which is characteristic of liquids. If the temperature were to rise, the molecules would gain even more energy, potentially transitioning into a gaseous state (steam).

Why an Iron Almirah is a Solid at Room Temperature

Now, let’s consider the iron almirah. The reasons it remains solid at room temperature are quite different from those of water:

• Atomic Structure and Bonding: Iron atoms are arranged in a tightly packed lattice structure, which is characteristic of solids. The metallic bonds between iron atoms are strong, providing rigidity and stability. This structure prevents the atoms from moving freely, which is why the almirah maintains its shape and does not flow like a liquid.
• High Melting Point: Iron has a high melting point (around 1,538 degrees Celsius). At room temperature, which is typically around 20-25 degrees Celsius, the thermal energy is far below what is needed to break the bonds holding the iron atoms together. Therefore, it remains solid under these conditions.

In summary, the state of a substance at room temperature is influenced by its molecular or atomic structure and the strength of the bonds between its particles. Water's unique hydrogen bonding allows it to be a liquid, while the strong metallic bonds in iron keep it solid.