What is the empirical formula for Barium chloride dihydrate​

A100-watt light bulb radiates energy at a rate of 100 j/s. (the watt, a unit of power or energy over time, is defined as 1 j/s.) if all of the light emitted has a wavelength of 525 nm , how many photons are emitted per second?

Which position represents spring in the southern hemisphere? a) b) c) d)

Give the orbital configuration of the phosphorus (p) atom.