What mass of lead(v) trioxonitrate(v)pb(No3)2 would be required to yield a gram of lead(v) chloride,pbcl2,on the addition of excess sodium chloride solution Nacl? (Pb=207,N=14,O=16, Na=23,Cl=35.5)
The International Union of Pure and Applied Chemistry (IUPAC) does not recognize the name you used for Pb(NO3)2. A name they recognize is lead(II) nitrate. There is no such compound as lead(v) nitrate. Also there is no such compound as Pb(v) chloride. I assume you want PbCl2 and that is named lead(II) chloride OR lead dichloride. I assume you're starting with Pb(NO3)2
Pb(NO3)2 + 2NaCl ==> PbCl2 + 2NaNO3
You want 1 gram PbCl2. How many moles is that? That's mols = grams/molar mass = 1/(278) = 0.0036
Convert mols PbCl2 needed to moles from Pb(NO3)2 using the coefficients in the balanced chemical equation. That's 0.0036 mols PbCl2 x (1 mol Pb(NO3)2/1 mol PbCl2) = 0.0036 x 1/1 = 0.0036 mols Pb(NO3)2. Convert that to grams. grams Pb(NO3)2 = mols Pb(NO3)2 x molar mass Pb(NO3)2 = ? g