I believe the correct answer is the second option. There will be two cobalt atoms in one formula unit of cobalt (III) oxide. It has a chemical formula of Co2O3. This compound is does not naturally occur so it is being synthesized. It is mostly used as bleaching agent.
Given the balanced equation:
( Reaction type : double replacement)
CaF2 + H2SO4 → CaSO4 + 2HFI
We can determine the number of grams prepared from the quantity of 75.0 H2SO4, and 63.0g of CaF2 by converting these grams to moles per substance.
This can be done by evaluating the atomic mass of each element of the substance, and totaling it to find the molecular mass.
For H2SO4 or hydrogen sulfate it's molecular mass is the sum of the quantity of atomic mass per element. H×2 + S×1 + O×4 = ≈1.01×2 + ≈32.06×1 + ≈16×4 = 2.02 + 32.06 + 64 = 98.08 u (Dalton's or Da) or g / mol.
For CaF2 or calcium fluoride, it's molecular mass adds 1 atomic mass of calcium and 2 atomic masses of fluoride due to the number of atoms.
Ca×1 + F×2 = ≈40.07×1 + ≈19×2 = 40.08 + 38 = 78.07 u (Da or Dalton's) or g / mol.
It's a chemical change because it's changing the object's property.
C; The Valence electrons spend more time around the atom of F
Answer:
1s*2 2s*2 2p*6
Explanation:
atomic number of neon is 10 so the s-shell contains 2 electron and p-shell contains 6
