Question

are the following examples of chemical or physical changes? (8 points) chemical change physical change a silver spoon tarnishing blowing a dandelion building a sand castle toasting bread

Explanation:

• A silver spoon tarnishing is a chemical change as silver reacts with sulfur - containing substances in the air to form silver sulfide, a new substance.
• Blowing a dandelion only changes the position of the dandelion seeds, no new substances are formed, so it is a physical change.
• Building a sand - castle only changes the shape of the sand, no new substances are created, thus it is a physical change.
• Toasting bread causes a chemical reaction in the bread due to heat, forming new substances like charred compounds, so it is a chemical change.

Answer:

A silver spoon tarnishing: Chemical change
Blowing a dandelion: Physical change
Building a sand castle: Physical change
Toasting bread: Chemical change