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Question
The concentration of sulfate in a sample of wastewater is to be determined by using gravimetric analysis. To a 100.0-mL sample of the wastewater is added an excess of calcium nitrate, forming the insoluble calcium sulfate (136.1g/mol) according to the balanced equation given below. The solid calcium sulfate is dried, and its mass is measured to be 0.7272g. What was the concentration of sulfate in the original wastewater sample?
SO42-(aq)+Ca(NO3)2(aq)→CaSO4(s)+2NO3-(aq)
A) 0.05343 M
B) 0.9897 M
C) 18.72 M
D) 1.872 M
E) 9.897 M
Answer
This answer is hidden. It contains 1 characters.
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