Find the molar mass of Strontium nitride, Sr3N2.

What is the molarity of a solution that is prepared by adding 57.1 g of toluene (c 7 h 8 ) (density = 0.867 g/ml) to a 250 ml volumetric flask, and then filling to the mark with benzene (c 6 h 6 ) (density = 0.876 g/ml)?

Write the chemical symbols for three different atoms or atomic cations with 27 electrons. asap!

George is a dalmatian puppy. describe what happens to light that allows you to see george’s black and white coat.