A layer of sandstone is found on top of a layer of shale. What most likely happened in this area?

Mud was deposited first, then sand.

Explanation:

This could have been a tidal mud flat succeeded by a sandy beach, or along the bed and course of a river with either mountain building upstream causing faster flow and carrying of mud farther away or the sea level falling with mud deposits being found closer to the new coastline. Hope this helps!

give me abc and i will get it for u.

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2