7. The hardness of water (hardness count) is usually expressed in parts per million (by mass) of CACO3, which is equivalent to milligrams of CaCO3 per liter of water. What is the molar concentration of Ca2+ ions in a water sample with a hardness count of 180 mg CaCO3/L?if we consider that water contains only Ca2+ ions. a) 18 x 10-4mol/l O b) 18 x 10-5 mol/l O c) 18 x 10-6 mol/I O d) 18 x 10-7 mol/l

7. The hardness of water (hardness count) is usually expressed in parts per million (by mass) of CACO3, which is equivalent to milligrams of CaCO3 per liter of water. What is the molar concentration of Ca2+ ions in a water sample with a hardness count of 180 mg CaCO3/L?if we consider that water contains only Ca2+ ions. a) 18 x 10-4mol/l O b) 18 x 10-5 mol/l O c) 18 x 10-6 mol/I O d) 18 x 10-7 mol/l

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter4: Stoichiometry

Section: Chapter Questions

Problem 4.97PAE

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