Question

Explain why water on a clean glass surface tends to spread out while mercury on the same surface tends to form drops. (Put differently, water wets glass while mercury does not)

Answer 1

This is so because , mercury atoms have a solid power of fascination among themselves and a feeble power of fascination toward solids . Consequently, they will in general frame drops.

Then again, water particles make intense points with glass. They have a feeble power of fascination among themselves and a solid power of fascination toward solids. Hence , they will in general spread out .

Answer 2

Hey mate,

◆ Reason-
1. For mercury,
- Mercury molecules will have strong force of attraction between themselves and weak attraction with solids.
- Here, angle of contact is quite big.
- Therefore, mercury doesn't wet the glass & the drop appears more bulged.

2. For water,
- Water molecules will have weak force of attraction between themselves and strong attraction with solids.
- There is acute angle of contact.
- Therefore, water wet the glass & the drop appears as flat.

Hope this is useful...