Which process is an example of a chemical change?

a metal railing rusting in damp weather
a piece of wood shrinking as it dries out
alcohol evaporating from a cotton swab
steam rising from a boiling pot of soup

Agas can holds 2.0 gal of gasoline. what is this quantity in cubic centimeters?

If you burn 10 kilograms of wood in a fire (combustion) what is the weight of the products after the fire has finished burning the wood?

The human eye contains a molecule called 11-cis-retinal that changes shape when struck with light of sufficient energy. the change in shape triggers a series of events that results in an electrical signal being sent to the brain that results in vision. the minimum energy required to change the conformation of 11-cis-retinal within the eye is about 164 kj/mol.