When you say that there is moisture in the air it pretty much means water in the air.
It is a physical change, as no new products have been formed.
The humidifier putting moisture into the air is a physical change. It involves adding water vapor, which is a change in the physical state of water from liquid to gas, without altering the chemical composition of the water molecule.
The color change of copper to green is a chemical change. This is due to the formation of a green patina on the surface of the copper, typically caused by oxidation reactions with the air and moisture.
The moisture is just water vapor, so you are getting a phase change from liquid to gas. Phase changes are physical changes. For a vaporizer to produce a chemical change it would have to do something drastic like convert the water in to H2 and O2.
The rusting of a gate is a chemical change. It occurs when the iron in the gate reacts with oxygen in the air and moisture to form iron oxide (rust), which is a new substance with different properties than the original iron.
the answer is yes because sodium is a solid right right so being exposed by a chemical is changed.
Difficult to be correct; chemists consider the higroscopy as a chemical phenomenon but I believe that some physicists has another opinoin.
Dry ice doesn't "turn into smoke". Dry ice causes moisture in the air to condense, forming fog. This is a purely physical, not chemical, change.
No. It is a physical change.
It is a chemical change as it releases gases into the air.
Tarnishing is a chemical change as it involves a reaction with the metal's surface, often due to exposure to air or moisture. Rusting is also a chemical change, specifically the oxidation of iron in the presence of oxygen and water. Both processes result in the formation of new compounds on the surface of the material.
Taking out silver spoons that are dull and have black dots on them involves a physical change, as the appearance of the spoons has changed but their chemical composition remains the same. The black dots are likely tarnish, which is a result of a chemical reaction with sulfur or oxygen in the air. Cleaning the spoons can restore their shiny appearance without altering the silver itself. Therefore, the tarnishing is a chemical change, but the act of taking them out is a physical change.
Rust formation is an oxidation reaction, which is a chemical change.