Why is coal not considered a mineral

What is the ima of the 1 st class lever in the graphic given? 2 3 0.5

In this chemical reaction, 325 grams of barium (ba) react completely. how many moles of lithium (li) are produced?

As we move from left to right across the periodic table, what is the general trend? a) atomic radii increase. b) electronegavitiy decreases. c) nuclear shielding increases. d) metallic character decreases.