Question

The active ingredient in a zinc nutritional supplement is ZnSO4 .7H2O (molar mass 287.58 g/mol). Ten zinc tablets containing a mix of the active ingredient and an inactive filler were ground and mixed together thoroughly. The total mass of these 10 tablets was 10.600 g. A 1.980 g sample of the finely ground tablets was dissolved in an acidic solution. The solution tion of (NH4)PO to the s the precipitation of ZnNH,PO4. The precipitate was filtered and dried, then ignited to produce 0.200 g of Zn2P20 mass-304.76 g/mol). What is the mass percent of ZnSO4·7 H2O in each tablet? (molar % ZnSO, . 7 H,O mass percent: What is the average mass of the active ingredient ZnSO4 7H20 and inactive filler in each tablet? ZnSo 7Ho mass g inactive filler mass

Answer 1

Zinc tablets(n)= 10 tablets

Total mass of 10 tablest = 10.600 g

For 1 tablet = 10.600/10 = 1.060 g

m = 1.980 g sample

For, mole of Zn2P2O7 = Mass/Molecular weight

= 0.200/ 304.76 = 0.00065625 moles

Mole of Zn = 2*0.00065625 = 0.0013125 mol of Zn

Mole of ZnSO4*7H2O --> 0.0013125 mol of active

Mass of active = Moles*Molecular mass

Moles of active = 0.0013125*287.58

Moles of active = 0.37745 g of active ingredients.

Percentage of ZnSO4.H2O = 0.37745 /1.980* 100

Percentage of ZnSO4.H2O= 19.06%

For average mass,

Average mass of active ingredient in 1 tablet:

Mass of table = 1.0600 g

which, 19.06 % is active = 1.0600*19.06/100

Mass =0.202036 g g is ZNSO4*7H2O

Inactive mass for each tablet = (1.0600-0.202036 )

Inactive mass for each tablet = 0.857964 g