1. If you started with 256 dimes and it took 12 years to decay to 16 dimes, what would be the half-life of the unstable element "Dimium"?

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?

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.