5Mg3(PO4)2
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Evaluate this exponential expression,8. (2 + 3)2 – 42

Write the symbol for every chemical element that has atomic number greater than 3 and atomic mass less than 12.0 u.

Silver tarnishes as silver metal reacts with hydrogen sulfide, h2s, in the air. in this reaction, dark silver sulfide, au2s, covers the surface of silver. when silver is polished, this coating of silver sulfide can be removed from the surface. this makes the silver shiny again. enter the coefficients that balance the tarnishing reaction equation. (type 1 for no coefficient.)