Question

Give 2 reasons to justify:
i.Water at room temperature is a liquid.
ii. An iron Almirah is solid at room temperature.

Answer 1

Hint:The physical properties of solid and liquid can help in answering this question. We will study the properties like shape, volume and their packaging. As we know that solids are tightly packed molecules.

Complete step by step answer: We will discuss both parts one by one.
In the part (a), we need to justify that water at room temperature is a liquid.
We need to know the properties of liquid state of matter in order to answer this question.
As we know there are 4 fundamental states of matter including solid, liquid, gas and plasma.
Here, we will talk about the properties of liquid state.
We can say that they do not have a fixed shape, but it has a fixed volume.
So, we can say that if it does not have a definite shape, it takes the shape of the container.
As we know, they are not very tightly packed and can flow readily.
Thus, the boiling point of liquid is greater than room temperature whereas the melting point of liquid is lower than room temperature.
Therefore, we can say that water at room temperature $(25^\circ C)$ has all these above mentioned properties of a liquid.
So, water at room temperature is a liquid.
Now, the next we have part (b), i.e. an iron almirah is solid at room temperature
To justify this statement, we need to know the properties of Solid state of matter.
We will discuss the properties of Solid state as follows:-
The solids have definite mass.
It does not change its shape on giving external force, thus it is rigid. It may be broken but no deformation can take place.
It has a definite shape and volume, and visible boundaries.
It is very tightly packed.
So, we can say that an iron (iron because of malleability) almirah shows all these properties of solid at room temperature. Thus, it is solid at room temperature.
In the last, we can conclude that water at room temperature is a liquid, and an iron almirah is solid at room temperature.


Note:If we talk about an iron almirah it is used in our homes, and we know that it does not flow. It is a solid. Talking about water, it is used by us daily. We know that it can flow, so it is a liquid. We have discussed the properties of solids and liquids. The properties of gases are:
Gases have no fixed shape and volume.
The particles are not tightly packed and flow readily than liquids.