The water in the cup slowly starts to freeze and then starts cracking slowly.
what type of change is this? chemical or physical?
This change is physical. The freezing and cracking of water is the result of a physical process, where the water molecules lose energy and arrange themselves into an ordered solid state. No new substances are formed during this process.
The process described, where the water in the cup slowly starts to freeze and then starts cracking slowly, is a physical change. This is because the substance (water) undergoes a change in its physical state from a liquid to a solid, without any alteration in its chemical composition.
The change described, where the water in the cup slowly starts to freeze and then starts cracking slowly, is a physical change.
To determine this, we can first understand the difference between physical and chemical changes.
Physical changes are changes in the physical properties of a substance, such as its shape, size, or state of matter, without altering its chemical composition. In this case, the water is changing from a liquid state to a solid state, which is known as freezing. It is still water, just in a different physical form. Additionally, the cracking of the frozen water does not involve any chemical reactions.
On the other hand, chemical changes involve the formation or breaking of chemical bonds, resulting in a change in the chemical composition of the substance. Examples of chemical changes include combustion (burning), rusting, or digestion.
In the given scenario, since there is no chemical reaction or alteration of the chemical composition of water, the change of the water from a liquid to solid state and the cracking are physical changes.