1.011)
Which of these substances will water dissolve?
A. lithium fluoride (an ionic substance)
B. carbon dioxide (a nonpolar molecule)
C. wax
D. all of these

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.