Question

Give reason
1. Iron almirah is a solid.
2. Ice being solid form of water
floats on water
3. The process of diffusion is
lifeline of aquatic organisms.
4. Writing on the blackboard if
kept for some days then
erased then the marks remain
on the blackboard.why

Answer 1

1. it is solid due to strong force of attraction.
2. As it cools further and freezes into ice, it actually becomes less dense. On the other hand, most substances are most dense in their solid (frozen) state than in their liquid state. Water is different because of hydrogen 
3. because aquati animals respire or take oxygen through dissolved water by diffusion
4.due to the solid diffusion