If an element has three isotopes with masses of 10.00 amu, 12.00 amu, and 16.00 amu with respective abundances of 10.00% , 60.00%, and 30.00% what is the average atomic mass of the element?

The alkali metals (group 1) consist of lithium (3), sodium (11), potassium (19), rubidium (37), cesium (55), and francium (87). they are soft, metallic solids with low densities and low melting points. based on the data shown in figure 1, how many valence electrons do alkali metals share?

Which statement describes james chadwick’s discovery.

In the millikan oil drop experiment they determined that every drop had a charge which was a while number multiple of -1.60x10^-19. if a drop has a total charge of -9.60x10^-19 then how many excess electrons are contained within the drop?