If the van urk reagent is used to test a sample and it turns bluish-purple, what drug does this indicate the presence of?

Why are pipes bursting in the in extremely cold weather?

Name the element in group 17, period 2. (periodic table)

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.