Physical changes!!
What are types of physical changes?
What are physical changes!!!
Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements
In a physical change, the internal make-up of the object (molecules) stays the same, even after the change — only its form changes. The resulting element can be reversed into the object before. Changes that can be reversed are called a Reversible Change.
Examples of physical changes
1.Ice melting involves a change from a solid to a liquid and the substances maintain the properties of water because the molecules never change.
2. Water boiling is a physical change as water molecules vibrate faster, they enter the gas phase and become water vapor.
3. Rubbing alcohol left uncovered will evaporate quickly into the air. It turns to a gas but maintains the properties of alcohol.
4. Hot molten iron is a liquid and when left to cool will from solid steel and can take many forms.
5. Dissolving sugar in water is a physical change. The solid sugar never loses its properties, the molecules become separated by water and the sugar can easily be recovered by evaporating the water.
Melting ice
Broken pencil
Boiling water
Difference between physical change and chemical change
There are several differences between a physical and chemical change in matter or substances. A physical change in a substance doesn't change what the substance is. In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.