Composition of mixture
Not what you're looking for?
1) The Zinc in a 1.200g sample of foot powder was precipitated as ZnNH4PO4. The strong heating of the precipitate yielded 0.4089g of Zn2P2O7. Calculate the mass percent of zinc in the sample of foot powder.
2. A mixture contains only sodium chloride and potassium chloride. A 0.1586g sample mixture was dissolved in water. It took 22.90mL of 0.100 M Silver I nitrate to completely precipitate all of the chloride present. What is the composition (by mass) of the mixture?
Purchase this Solution
Solution Summary
The answers calculate
1) the mass percent of zinc in the sample of foot powder 2) composition (by mass) of the mixture of sodium chloride and potassium chloride
Solution Preview
See attached file in which formatting is preserved.
The Zinc in a 1.200g sample of foot powder was precipitated as ZnNH4PO4. The strong heating of the precipitate yielded 0.4089g of Zn2P2O7. Calculate the mass percent of zinc in the sample of foot powder.
Atomic weights
Zinc Zn 65.38
Phosphorus P 30.97376
Oxygen O 15.9994
Molecular weight of Zn2P2O7= 304.70332 =2*65.38+2*30.97376+7*15.9994
304.70332 g of Zn2P2O7 contains 2*65.38=130.76 g of Zinc
Therefore 0.4089 g of Zn2P2O7 contains 0.17547 (=0.4089*130.76/304.70332) g of Zinc
Thus 1.200 g sample of foot powder contains 0.17547 g of Zinc
Mass percent of Zinc= 14.62% =(0.17547/1.2)
2. A mixture contains only sodium chloride and potassium chloride. A 0.1586g sample mixture was dissolved in water. It took 22.90mL of 0.100 M ...
Purchase this Solution
Free BrainMass Quizzes
General Chemistry - Classification of Matter
This test will assess your knowledge on the classification of matter which includes elements, compounds and mixtures.
Match Elements with their Symbols
Elements are provided: choose the matching one- or two-letter symbol for each element.
Functional groups in Organic Chemistry
You will be tested on the names of functional groups in Organic Chemistry. It is very important to know the functional groups to understand Organic reactions.
Thermochemistry
The quiz helps in revising basic concepts about thermochemistry.