Helppp 88.0 grams of Boron, how many atoms of Boron (B) are present?

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?

Compared with the freezing-point depression of a 0.01 m c6h12o6 solution, the freezing-point depression of a 0.01 m nacl solution is

At 450 mm hg a gas has a volume of 760 l, what is its volume at standard pressure