Physical
By melting the two metals and putting them together, you are creating an alloy, a homogenous mixture. The process does not change any atoms, so it is not a chemical reaction, but a physical change.
Crumpling tin foil is a physical change, not a chemical change. This process alters the shape and texture of the foil but does not change its chemical composition. The material remains aluminum regardless of how it is manipulated, meaning no new substances are formed.
Tearing a piece of tin foil is a physical change because the substance's chemical composition remains the same before and after tearing. The appearance and physical structure of the tin foil may change, but no new substances are formed during the tearing process.
Yes, it is, because the chemical composition of the outside changes due to oxydation.
Crumpling tin foil is a physical change. This process alters the shape and structure of the foil without changing its chemical composition. The material remains aluminum regardless of its form, and no new substances are created during crumpling.
Examples: valence (II or IV), soluble in acids and alkalis.
Darass
A physical change
Physical change of the paint, not the door.
it is a chemical change
Crushing charcoal into powder is a physical change, as it alters the size and shape of the charcoal without changing its chemical composition.
An acid is a chemical compound, not a physical or chemical change.