Calculate the ionic strength in a solution that contains 0.010 mol KCl, 0.005 mol MgCl2, 0.002 mol MgSO4, and 100g H2O.

Describe a low carbohydrate diet and a low fat diet. Be sure to describe them at the molecular level and relate them to the pathways we’ve studies in this class. Compare and contrast these two with a severe caloric deficit diet (i.e. starvation). Which of the two diets most closely resembles starvation in terms of metabolic pathways.

A very long pipe is capped at one end with a semipermeable membrane. How deep (in meters) must the pipe be immersed into the sea for fresh water to begin to pass through the membrane? Assume the water to be at 20.0°C and treat it as a 0.700 M NaCl solution. The density of seawater is 1.03 g/cm3 and the acceleration due to gravity is 9.81 m/s2.

Calculate the pH of each of the following solutions:

a. 0.00184M H+

b. 6.23 x 10-4M HCl

c. 3.18 x 10-2M NaOH

d. 4.12 x 10-4M NaOH

20. The chemical equation for the reaction between hydrochloric acid and potassium hydroxide is HCl(aq) + NaOH(aq) NaCl(aq) + H2O(l)

When 25 mL of 1.0 M HCl (36.5 g/mol) is mixed with 25 mL of 1.0 M NaOH (40 g/mol), the temperature change of the mixture is 6.9 oC. The density of the mixture is 1.00 g/mL and the specific heat of the solution is 4.18 J/ g oC. What is the enthalpy change for this reaction?

What is the mole fraction of O2 in a mixture of 15.1 g of O2, 8.19 g of N2, and 2.47 g of H2?

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Part B

Part complete

What is the mole fraction of N2 in a mixture of 15.1 g of O2, 8.19 g of N2, and 2.47 g of H2?

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Part C

Part complete

What is the mole fraction of H2 in a mixture of 15.1 g of O2, 8.19 g of N2, and 2.47 g of H2?

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What is the partial pressure in atm of O2 of this mixture if it is held in a 15.20 −L vessel at 16 ∘C?

What is the partial pressure in atm of N2 of this mixture if it is held in a 15.20 −L vessel at 16 ∘C?

What is the partial pressure in atm of H2 of this mixture if it is held in a 15.20 −L vessel at 16 ∘C?

Buffer capacity is a measure of a buffer solution\'s resistance to changes in pH as strong acid or base is added. Suppose that you have 115 mL of a buffer that is 0.340 M in both propanoic acid (C2H5COOH) and its conjugate base (C2H5COO–).

Calculate the maximum volume of 0.450 M HCl that can be added to the buffer before its buffering capacity is lost.

Carbonic acid (H2CO3) is a weak diprotic acid with Ka1=4.43×10−7 and Ka2=4.73×10−11. When sodium bicarbonate (NaHCO3) is titrated with hydrochloric acid (HCl), it acts as a weak base according to the equation

NaHCO3(aq)+HCl(aq)→H2CO3(aq)+NaCl(aq)

Part A

What volume of 0.190 M HCl is required for the complete neutralization of 1.70 g of NaHCO3 (sodium bicarbonate)?

Express your answer to three significant figures and include the appropriate units.

Part B

What volume of 0.120 M HCl is required for the complete neutralization of 1.80 g of Na2CO3 (sodium carbonate)?

Express your answer to three significant figures and include the appropriate units.

Part C

A sample of NaOH (sodium hydroxide) contains a small amount of Na2CO3 (sodium carbonate). For titration to the phenolphthalein endpoint, 0.170 g of this sample requires 23.98 mL of 0.100 M HCl. An additional 0.700 mL of 0.100 M HCl is required to reach the methyl orange endpoint. What is the percentage of Na2CO3 by mass in the sample?

Express your answer to three significant figures and include the appropriate units.

Ammonium chloride is salt produced from the reaction of monobasic ammonia and chlorine. Ammonia has a pKb of 4.76. Calculate pH of of solution by adding 100g NH4Cl to 100ml of water. Assume total vol of sol is 100 ml. Ksp of NH4Cl is 30.9. Is this a saturated or unsaturated sol

A 236.4 mL sample of water contains 0.0294 g of NaCl. Calculate the concentration in ppm.

concentration = ___ ppm

Demonstrate, how to calculate the drift time in a TOF mass spectrometer, if the acceleration voltage is known.

a solution prepared by mixing 60ml of .1m agno3 and 60ml 0f .1m tino3 was titrated with .2M nabr in a cell containing a silver indicator electrode and a reference electrode of constant potential .175 v. the reference electrode is attached to the positive terminal of the potentiometer, and the silver electrode is attached to the negative terminal. the solubility constant of tibr is ksp=3.6x10^-6 and the solubility constant of agbr is ksp=5x10^-13.

AgBr precipitates first

the following expression shows how the cell potential E depends on {ag+]      E=.175-[.799-.05916log(1/[ag+])]

1. Calculate the first and second equivalence points of titration.

2. what is the cell potential when the following volumes of .2M nabr have been added: a)1ml, b)16.8ml, c)29ml, d)29.9ml, e)30.3ml, f)46.8ml, g)60ml, h)63.6ml