Why does a drop of water form a sphere

There are 6.022, 104 atoms of hg in 1 mole of hg the number of atoms in 45 moles of hg can be found by multiplying 4.5 by 6.022, 102 which is the number of atoms in 4.5 moles of hg, correctly written in scientific notation with the correct number of significant figures? 0 21,109 0 21,100 271, 1024 27.099, 100 mark this and retum save and exit submit

Why do cells appear different in distilled water than they do in 10% salt water?

The molar mass of iron(fe) is 55.8 g/mol. what is the mass in grams of 2.25 moles of iron?