1. In a laboratory experiment, an undergraduate student collected a sample of ammonium phosphate. If the sample contains 9.52 x 1025 molecules, how many grams of the sample did he
collected?

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.