“Where can we apply acoustic levitation in real life?” (please help me im in a middle of a final exam)

What does the mass of 0.7891 mol of ferric oxide (fe2o3)

How many moles of oxygen gas are produced from the decomposition of six moles of potassium

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.