Answer:
1. Proton = electron if the element is not in an ionic state
proton = atomic number
1) moles = mass/mR
CaCO3 Mr = 40 + 12 + (16×3)
= 52 + 48
= 100
mass = 15
so the moles would be 15 ÷ 100
which is 0.15 moles of CaCO3
2) moles = mass ÷ Mr
Mr of Al2O3 = 27 + (16×3)
= 27 + 48
= 75
mass = 204
so the moles would be 204/75 which is 2.72 moles of Al2O3
all i know is that the formula for triangles is base times hight divided by two, so add in a number to replace the missing number, multiply it by 55 and divide the answer by two. hope this helps and i really hope you get it right! or that im right...
Mass / density = volume
321g / 0.84 = 382.142857