Explain the connection between periods and energy levels.

If 1.63 times 10 negative 4 of helium dissolves in 100.0g of water, what is the concentration in parts per million

The picture represents the process that produces most of the energy used by living organisms on earth. which process is represented in the picture? a) the magnetic attraction between two hydrogen nuclei. b) the fusion of hydrogen nuclei to produce a helium nucleus in the core of the sun. c) the fission of hydrogen nuclei to produce a helium nucleus in the core of the sun. d) the chemical reaction between hydrogen nuclei to produce a helium nucleus in earth's atmosphere.

What element has similar physical and chemical properties as boron.