What is the molarity of a solution that contains 4.13g of magnesium bromide in 0.845 l of solution

Great amounts of electromagnetic energy from our sun and other bodies in space travel through space. which is a logical conclusion about these electromagnetic waves? their energy must be very their frequency must be very low these waves can travel without a medium they only travel through a vacuum of space

Chemistry worksheet - i am not sure what they are asking for exactly?

Use the periodic table to find the molar mass of each element. molar mass h = g/mol molar mass s = g/mol molar mass o = g/mol