can get the answer for all these questions

1. Calculate the pH in a solution that is 0.98 M in NaC2H3O2 and 0.56 M in HC2H3O2. (Ka = 1.8 x 10–5)

2. Given 15.0 mL of a buffer that is 0.87 M in HOCl and 0.95 M in NaOCl, what is the pH after 2.0 mL of 0.10 M NaOH has been added? (Ka for HOCl = 3.5  10–8)

3. The molar solubility of Mg3(PO4)2 is 6.26 x 10–6 M. Calculate the value of Ksp for Mg3(PO4)2.

4. A 20.00-mL solution of 0.120 M nitrous acid (Ka = 4.0 × 10–4) is titrated with a 0.215 M solution of sodium hydroxide as the titrant. What is the pH of the acid solution at the equivalence point of titration? (if needed: Kw = 1.00 × 10–14)

5. You have two salts, AgX and AgY, with very similar Ksp values. You know that Ka for HX is much greater than Ka for HY. Which salt is more soluble in acidic solution? (2pts) [MUST GIVE SOME EXPLAINATION OF ANSWER FOR CREDIT]

a) AgX

b) AgY

c) They are equally soluble in acidic solution.

d) Cannot be determined by the information given.

e) None of these (A-D).

6. Which of the following solid salts should be more soluble in 1.0 M HCl than in water? (2pts) (circle all that apply) [MUST GIVE SOME WORK/EXPLAINATION OF ANSWER FOR CREDIT] a) Na2CO3 b) KCl c) AgBr d) KNO3 e) RbF

9.What is the solubility (s) of Mg(OH)2 (Ksp = 8.9 x 10–12) in 1.0 L of a solution buffered (with large capacity) at pH 9.85

7. The Ksp for Co3(AsO4)2 is 6.8 x 10–29. When 0.20 mL of 0.010 M Na3AsO4 is mixed with 0.20 mL of 0.010 M CoCl3, will a precipitate form?

8. What is the maximum concentration of iodide ions that will precipitate AgI but not PbI2 from a solution that is 6.7  10–3 M each in Ag+ and Pb2+? For AgI, Ksp = 1.5 × 10–16 and for PbI2, Ksp = 1.4 × 10–8 .

10. Calculate the concentration of aqueous ammonia necessary to initiate the precipitation of chromium(III) hydroxide from an equilibrium solution 0.050 M solution of CrBr3. Ksp = 3.0 x 10-29 Kb = 1.8 x 10-5

How much heat in kilojoules is evolved in converting 2.00 mol of steam at 140 ∘C∘C to ice at -20.0 ∘C∘C? The heat capacity of steam is 1.84 J/g∘CJ/g∘C and that of ice is 2.09 J/g∘CJ/g∘C.
Remember that if heat is leaving the system, then q is a negative number and if heat is entering the system, then q is a positive number.

1. a) Does a precipitate form when 0.200 L of 0.15 M Ca(NO₃)₂ is mixed with 0.100 L of 0.120 M NaF? At experimental temperature, K_sp of CaF₂ = 3.9 x 10^-11

b) Calcium hydroxide, Ca(OH)₂, is an important component of many mortars, plasters and cements. Calculate the molar solubility of Ca(OH)₂ in water if K_sp is 6.5 x 10^-6.

c) What is the solubility of Ca(OH)₂ in a 0.20 M solution of Ca(NO₃)₂? K_sp of Ca(OH)₂ is 6.5 x 10^-6

1) If the Ka of a monoprotic weak acid is 2.1

How many grams of NaH₂PO₄ and how many grams of Na₂HPO₄ are needed to prepare 2.0 L of 1.50 M “phosphate buffer” with a pH of about 8.00.

You are given:

For salt form of a weak acid NaH₂PO₄ or weak acid H₂PO₄^-, pK_a = 7.21 and K_a = 6.2 x 10^-8

1 mol Na₂HPO₄ = 142 g Na₂HPO₄

1 mol NaH₂PO₄ = 120 g NaH₂PO₄

Select one:

a. Mass of NaH₂PO₄: 35.5 g and Mass of Na₂HPO₄: 276.1 g

b. Mass of NaH₂PO₄: 70.6 g and Mass of Na₂HPO₄: 392.9 g

c. Mass of NaH₂PO₄: 50.2 g and Mass of Na₂HPO₄: 366.5 g

d. Mass of NaH₂PO₄: 37.9 g and Mass of Na₂HPO₄: 312.8 g

e. Mass of NaH₂PO₄: 75.3 g and Mass of Na₂HPO₄: 408.1 g

A mixture solution of Co(II) and Ni(II) shows an absorbance of 0.500 at 500 nm. What percentage of incident light is absorbed by the solution?

Under the given conditions if 20% of the absorbance is ascribed to the contribution of Co(II), what will the absorbance of Ni(II) be?

An atom of an element weighs 5.88 × 10-23 g. What is the atomic mass of this element in atomic mass units?

1. When chromium metal is added to nitric acid, the following reaction takes place Cr (s) + 6 HNO₃ (aq) → Cr(NO₃)₃ (aq) + 3 H₂O (l) + 3 NO₂ (g) Calculate the volume of NO₂ gas collected over water at 40.0 °C when 35.1 g of chromium is added to excess nitric acid if the total pressure is 675 torr. The vapor pressure of water at 40.0 °C is 55.3 torr.

and

2. How many grams of Al were reacted with excess HCl if 6.28 L of hydrogen gas were collected at STP in the following reaction? 2 Al (s) + 6 HCl (aq) → 2 AlCl₃ (aq) + 3 H₂ (g)

1.

An aqueous solution of calcium hydroxide is standardized by titration with a 0.171 M solution of hydroiodic acid.

If 27.0 mL of base are required to neutralize 10.6 mL of the acid, what is the molarity of the calcium hydroxide solution?

_______M calcium hydroxide

An aqueous solution of hydrobromic acid is standardized by titration with a 0.162 M solution of calcium hydroxide.

If 23.9 mL of base are required to neutralize 27.6 mL of the acid, what is the molarity of the hydrobromic acid solution?

_______M hydrobromic acid

2.

A 12.2 g sample of an aqueous solution of hydroiodic acid contains an unknown amount of the acid.
If 24.1 mL of 0.305 M barium hydroxide are required to neutralize the hydroiodic acid, what is the percent by mass of hydroiodic acid in the mixture?

______% by mass

A 11.1 g sample of an aqueous solution of hydrobromic acid contains an unknown amount of the acid.
If 22.4 mL of 0.467 M barium hydroxide are required to neutralize the hydrobromic acid, what is the percent by mass of hydrobromic acid in the mixture?

______% by mass

The human body contains 0.20% natural potassium. K-40 represents 0.0117% of naturally occurring potassium. 1. What is the radioactivity due to K-40 for a person weighing 70 kg? 2. What is the radioactivity due to K-40 for all people on Erath?

by comparing the instrumental design of a spectrophotometer and the spectrofluorometer, why does the emission spectrum of the blank have well defined peaks while the absorption spectrum is nearly flat?

(hint how do you define absorbance)

What are some medical or commercial applications of gases, and how are gas laws a part of those applications? Post a thorough initial response to the discussion question (at least 7-10 sentences, or approximately 150-200 words).