Question

28 > The active ingredient in a zinc nutritional supplement is ZnSO, 7H, (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 11.285 g. A 2.056 g sample of the finely ground tablets was dissolved in an acidic solution. The solution was neutralized with ammonia and subsequently warmed in a water bath. Addition of (NH), PO, to the solution resulted in the precipitation of ZnNH, PO, The precipitate was filtered and dried, then ignited to produce 0.154 g of Zn, P,0, (molar mass = 304.76 g/mol). What is the mass percent of ZnSO, 7H,O in each tablet? mass percent: % ZnSO, -7H,0 What is the average mass of the active ingredient ZnSO, 7H,0 and inactive filler in each tablet? mass: gZn50, 7H,0 mass: ginactive filler

Answer 1

mass of ZN z 22 y = 0.154 g Molar mass of ZMP07 = 304.76 g/mol. Atomic mass of an is 65.38 . 4.76 g of Boz amount of an contains = (65.38x2) - 1301769 Therefore, in 0,154 g of zm ago there is/130.76 0.154) (304.76 = 0.06607 g zn So, 0.06607 g of zn is present in 0.154 g of ZU₂ P2 07 mass of each tablet = 11.285 = 1.1285 g 10 Each tablet contains mixture of ansoy and A an inactive filer. 7H₂6 Molar mass of anson. 7 H₂O is 287.58 g/mol 65.38 g of zn contains in 287.58 g of En son 7H₂O So, 0.06607 g of an contains in / 287.58 X0606607), 65.38 i = 0.2906 g of zn sog. 740

So, 0.06607 g of an is present in 0.2906 g of zusog i7H2O mass of sample = 2,056 g Therefore in 2.056 g of tablet sample there is 0.2906 g of an son, 7Hollan Hence in l. 1285 g of tablet (mass of each tablet) there is (0.2906 x 1.1285) g of n sog. Ito hot (2.056. - 0. 159513 g of an Son 7 H₂6 There fore each tablet contains of ZnSO4.7H₂O 01159513 g Mass of each fablet = 1.1285 g

Mass percent of zusog, 7H0 in each tablet mass of zuso. 720 x 100 Total mass of each tablet - (0.159513 & ad . 671285 * 100 % 1:1285 - 14.1349 % Mass percent = (14.1349 %. Znso.7H2O In each tablet there is (1.1285-0.159513) 9 of inactive filler - 0.9689 g of inactive filler A mass = [0.189513] g zu sop. 742 mass=[ 0.9689] g inactive filler.