Calculate the mass of 6.9 moles of nitrous acid (HNO2). Show your work by including all values used to determine the answer. Round to 2 Significant Figures for full credit. (Molar mass of H = 1.0079 g/mol; N = 14.0067 g/mol; O = 15.9994 g/mol)
the mass of 6.9 moles is 33

Significant figures are digits read directly from the measuring instrument plus one more digit, which is __ by the observer.

What is the percent by mass of oxygen in fe2o3

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.