How are solids and liquids different than gases in terms of volume changes

Summarize possible ways in which phases of matter could combine to form a solution.

In which reaction is precipitation occurring?

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.