Question

A. You wish to prepare 198 grams of 10.3 % Na₃PO₄. How many grams will need of sodium phosphate and how many mL of water? Assume that the density of water is 1.00 g / ml.

B. If 20.5 grams of an aqueous solution of cobalt(II) sulfate, CoSO₄, contains 2.84 grams of cobalt(II) sulfate, what is the percentage by mass of cobalt(II) sulfate in the solution?

C. An aqueous solution of lead nitrate, Pb(NO₃)₂, contains 8.74 grams of lead nitrate and 17.5 grams of water. What is the percentage by mass of lead nitrate in the solution?

D. An aqueous solution is 1.00% by mass ethanol, CH₃CH₂OH, and has a density of 0.996 g/mL. What is the molarity of ethanol in the solution?

E. An aqueous solution is 22.0% by mass silver nitrate, AgNO₃, and has a density of 1.22 g/mL. What is the molarity of silver nitrate in the solution is?

F. An aqueous solution of 15.7 M ammonia, NH₃, has a density of 0.892 g/mL. What is the percent by mass of NH₃ in the solution?

Answer 1

Following is my Solution to the First full question i.e. Question: A)

The Answers are found to be the following:

- Grams of sodium phosphate (Na₂PO₄) = 20.39 gm

- Volume (mL) of Water (i.e. H₂O) = 177.61 mL

The solution to the above results, are discussed/explained below: (i.e. in image format):

Correction: In the above solution at one "line" of the answer, Sodium Phosphate has been incorrectly mentioned as Na₂PO_4....

Correct representation of Sodium Phosphate is the following:

Sodium Phosphate is written as Na₃PO₄