An element with a full outer shell of valence electrons is called a

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Asample of tin (ii) chloride has a mass of 0.49 g. after heating, it has a mass of 0.41 g.  what is the percent by mass of water in the hydrate?   %

The diagram shows the relationship between scientific disciplines.the names of some scientific disciplines have been removed from the boxes. which scientific discipline belongs in the blue box? a.physics b.biology c.chemistry d.metallurgy