Hi, i think the correct answer would be D .
Fluorine - Seven electrons of it's own.
Lithium would give up one electron, so there for, fluorine is then left with eight.
Let's hope she didn't watch it without me or i will never be speaking to her again :))
<span>PbO
Let's look at each of the 4 compounds and see what's needed.
PbO.
* Oxygen has a valance shell that's missing 2 electrons and wants to get those 2 elections. Lead donates them, so you have a Lead (II) ions. This is a correct choice.
PbCl4
* Chlorine wants to grab 1 electron to fill it's valance shell and Lead donates that election. However, there's 4 chlorine atoms and every one of them wants and electron, and lead is donating all 4 of the desired electrons making the Lead (IV) ion. So this is a bad choice.
Pb2O
* Oxygen still wants 2 electrons and gets them from the lead. But there's 2 lead atoms and each of them donates 1 election making for 2 Lead(I) ions. So this too is a bad choice.
Pb2S
* Sulfur is in the same column of the periodic table as oxygen and if this compound were to exist would have similar properties as Pb2O and would have Lead(I) ions. So this is a bad choice.</span>
H2SO4 ---> 2H^+ + SO4^2-
Hence n H+ = 9 mols
Mass of H = nM = (9*1) = 9g
Alternately
mass of H2SO4= nM= 4.5*98= 441
Mass of H= mass h2so4 * molar mass of H/molar mass of h2so4
Mass of H= 441 * 2/98 = 9g