Q: A chemist attempts to prepare some crystals of borax (sodium tetraborate, Na,B4O7.10H2O) by dissolving 100g of Na,B40, in 200 g of boiling water. He then carefully cools the solution slowly until some NazB407.10H2O crystallizes out. Calculate the g of NazB407.10H2O recovered in the crystals per 100 g of total initial solution (Na2B,0, plus H2O) if the residual solution at 55°C after the crystals are removed contains 12.4% NazB4O7.

Q: A chemist attempts to prepare some crystals of borax (sodium tetraborate, Na,B4O7.10H2O) by dissolving 100g of Na,B40, in 200 g of boiling water. He then carefully cools the solution slowly until some NazB407.10H2O crystallizes out. Calculate the g of NazB407.10H2O recovered in the crystals per 100 g of total initial solution (Na2B,0, plus H2O) if the residual solution at 55°C after the crystals are removed contains 12.4% NazB4O7.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter15: Acid–base Equilibria

Section: Chapter Questions

Problem 98AP

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