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Calcium oxalate, CaC2O4, is a common component of kidney stones and dissolves according to: CaC2O4(s)        Ca2+(aq)+C2O42−(aq) Given that the solubility product constant Ksp=2.3×10−9 Explain how high concentrations of calcium or oxalate ions in urine can lead to kidney stone formation. If the concentration of C2O42- in urine is 1.0×10−4 , calculate the maximum Ca2+ concentration before precipitation occurs. Show calculations on the scratch paper.

What is the pH of a 100 mL solution made from 46.2 mL of 0.050 M nitric acid and water. Show work in scratch paper

The standard molar entropy of lead(II) bromide (PbBr2) is 161 J/mol K. What is the entropy of 2.45 g of PbBr2? Show your work on the scratch sheet

Which of the following is not a buffer system and why? A solution containing roughly equal concentrations of a) ammonia and ammonium         b) methyl amine and methyl ammonium  c) perchloric acid and perchlorate     d) hydrofluoric acid and fluoride Explain

What is the pH of a 0.15 M solution of ammonium bromide? The Kb value for ammonia is 1.8X10^-5  Show work on the scratch paper

You have been given an assertion statement and a reason. Select from A- D to locate the correct statement ? A) Both assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the assertion (A). B) Both Assertion (A) and reason (R) are true but Reason (R) is the not the correct explanation of the assertion (A). C) Assertion (A) is true, but Reason (R) is false. D) Assertion (A) is false, but Reason (R) is true. Assertion (A): At the triple point, the vapor pressure of the substance is equal for all three phases.Reason (R): The Clausius-Clapeyron equation can be used to describe pressure changes along all phase boundaries.

The enthalpy and entropy of vaporization of a liquid A are 38.6 kJ/mol and 109.8 J/mol · K, respectively. The boiling point of the liquid , in °C [blank1].  We know this because [blank2] Show your work on the scratch paper

The entropy of vaporization of water is 109.0 J/mol K. What is the enthalpy of vaporization of water at its normal boiling point? Enter the answer and show the math on the scratch paper.

How does the concentration of Co3+ ions change in a saturated solution when solid Co(OH)3 is added to a solution in equilibrium ?Explain in the scratch sheet including all reactions

The oxidation number of P in phosphate is _____