Just 2 valence electrons.
Hydrogen already has one to start with, as well. With the exception of hydrogen and helium, all other atoms need 8 valence e-
I would expect fine salt to fully dissolve by the end of 45 minutes. Since the other types of salt are not fine and tiny, they would take longer to dissolve
Often, the rock layers bookending the mass extinction are noticeably different in their compositions. These changes in the rocks show the effects of environmental disturbances that triggered the mass extinction and sometimes hint at the catastrophic cause of the extinction
The wavelength and frequency of light are closely related. The higher the frequency, the shorter the wavelength. ... The equation that relates wavelength and frequency for electromagnetic waves is: λν=c where λ is the wavelength, ν is the frequency and c is the speed of light.