Physical changes alter the form or state of matter without changing its chemical composition. These changes are typically reversible, like melting, freezing, and boiling.
Physical changes involve changes in physical properties without producing new substances. Examples include boiling water, folding paper, and molding clay.
Chemical changes result in the formation of new substances with different chemical properties. These changes are often irreversible, like rusting iron or burning wood.
Nature of Chemical Changes
Chemical changes involve a substance losing its original properties and forming new substances. These changes cannot be reversed by physical methods and include gas evolution, color change, and heat or sound production.
Heating water, folding paper, molding clay, cutting wood, crushing paper, and mixing salt in water. These do not produce new substances and are reversible.
Burning paper or wood, cooking vegetables, digestion, and weathering of rocks. For more educational resources, visit eTutorWorld.com to download 7th grade science worksheets.