dissolving salt in water. the salt dissapears but if you evaporate the water,
salt will be remained.
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Answer #2:
The answer is that a substance never "disappears". It may become imperceptible
to your senses, or it may move to another place outside of the region that you
are monitoring, but no substance in any realm that you can observe ever passes
into "nothingness".
The semi-exception is the situation in which mass becomes energy, but even
then, although some mass has apparently "disappeared", some energy has
apparently "appeared" ex nihilo, and if you understand the mass/energy
equivalence, then you understand that even there, nothing has appeared
or disappeared.
A physical change that does not produce a new substance is called a reversible change. This means the change can be undone by reversing the process, such as melting or freezing.
A change that does not make a substance into a new substance is called a physical change. In physical changes, the physical properties of the substance may change, such as shape, size, or state (solid, liquid, gas), but the chemical composition remains the same.
A change that alters the form of a substance without changing it into another substance is called a physical change. This type of change does not involve a change in the chemical composition of the substance, only its physical appearance. Examples include changes in state (solid to liquid) or changes in shape (cutting or crushing).
This is called a change in the physical state of the substance. For example formation of ice from water is a change in the physical state of water.
Chemical reaction.
A physical change does not change the substance.
A physical change that does not produce a new substance is called a reversible change. This means the change can be undone by reversing the process, such as melting or freezing.
A change that does not make a substance into a new substance is called a physical change. In physical changes, the physical properties of the substance may change, such as shape, size, or state (solid, liquid, gas), but the chemical composition remains the same.
It's called a physical change.
Physical change
A change that alters the form of a substance without changing it into another substance is called a physical change. This type of change does not involve a change in the chemical composition of the substance, only its physical appearance. Examples include changes in state (solid to liquid) or changes in shape (cutting or crushing).
It's called a physical change.
This is called a change in the physical state of the substance. For example formation of ice from water is a change in the physical state of water.
a physical change.
a physical change is a change in any physical property of a substance, not in the substance itself
a physical change is a change in any physical property of a substance, not in the substance itself
When a substance changes but still retains its original properties, the change is called a physical change. If it didn't retain its original properties, then it went through a chemical change.