How much air is in the sun

For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

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?

0.2348 grams of pbcl2 used to form 44.0 ml of solution.