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How many grams of oxygen gas are contained in a 15 l sample at 1.02 atm and 28°c? show your work.

How will the volume of a gas be affected if the pressure is tripled, but the temperature remains the same?

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.