One water sample form a home in Flint had lead levels of 13,200 ppb (part per billion) (See Chemical & Engineering News; February 11, 2016; vol. 97; issues 7; pp 26-29). All samples from the same home had more than 300 ppb, even after flushing. The average of several samples that were taken from the home was 2,000 ppb. If ppm is equivalent to micrograms/liter, then how many grams of lead were in each liter of water? Why is it a problem when too much lead is in drinking water?

Your task related to this topic is to work out what the analogous“linear transport relation”should be for describing chemistry in the Onsager picture. You need to identify the “force,”the “flux,”and the “transport coefficient.”No need to worry about how chemistry would interact with other forces and/or fluxes, just an expression describing a chemical reaction itself as a “dissipative channel”that would represent a diagonal term in the matrix of Onsager transport relations (the off-diagonal terms would describecoupling between different forces and fluxeswhile the diagonal terms are all the traditional equations that came before Onsager). Correct answers will refer to single chemical reactions, bonus points if you can write the expression fora chemical reaction network with a generic number of reactions taking place inside it. There is one point that I need to notebefore you get started with this problem, however. The problem is almost as simple as just looking at the three equations relating flux and force, figuring out which state variables would be used for chemistry (hope that’s obvious but I gave the answer in the notes above if not) and then deciding whether you want to use a conductance or resistance coefficient and just “writing it down.”There is one complication you will need to puzzle out, however, which is probably also the reason that there isn’t a law of this sort already defined for chemical reactions. I’ll give you a hint: it has to do with themeaning of the statement chemistry teachers say“don’t confuse thermodynamics with kinetics,”which I told you really meant “don’t confuse a barrier height with a well depth,”but we could also say “don’t confuse equilibrium thermodynamics with kinetics.”OK, that’s the only complication that makes the answer to the question atall different than the other three equations and once you get it then you should be able to just write downthe answer.

Quinine, C20H24N2O2, occurs naturally in the bark of the cinchona tree and was the first effective treatment for malaria. It is a diprotic base with Kb values of (the acidic protons are shown in red) C20H24N2O2 + H2O HC20H24N2O2+ + OH- Kb2 = 1.0 × 10-6 HC20H24N2O2+ + H2O H2C20H24N2O22+ + OH- Kb1 = 1.58 × 10-10

a) The recommended IV dose of quinine is 0.800 g/kg, that is, 0.800 g of quinine per 1 kg of water. If we assume that the density of the solution is 1.00 g/mL, what is the pH of this solution? The molar mass of quinine is 324.412 g/mol. For simplicity, abbreviate C20H24N2O2 as Q.

b) 100 mL of the solution from part a is then titrated with a solution of 0.010 M HCl. How many mL of HCl solution is required to reach the first equivalence point?

c) What is the pH at the first equivalence point?

d) What is the pH when 32.00 mL of HCl has been added?

e) What is the pH at the second equivalence point?

f) Quantitatively draw the resulting titration curve on the axes below. Be sure to label both axes, equivalence points and buffer regions. Be as accurate as use can and make use of your results for parts a-e. g) The pH in the stomach is often quite low, between 2 and 3. What species of quinine is predominant at a pH of 2.5?

h) The pH of blood is buffered at 7.4. What species of quinine is predominant at this pH?

Neutralization Reactions

In a clean, small container (glass vial or small paper cup), place about ten drops of an ammonia cleaner and two “squirts” of cabbage juice indicator.

Use a clean medicine dropper and count the number of drops of vinegar required to change the color of the solution from green to purple.

Repeat the above tasks with pickle juice or some solution that you found to have an acid pH slightly higher than vinegar.

Create a data table that summarizes your results of the two titrations.

Neutralization Reactions – comparison of two acid solutions neutralizing a base cabbage juice + ammonia solution

Insert Table Here

In the titration of ammonia solution with vinegar, and with another acid solution with a slightly higher pH value, how did the amounts needed for the neutralization of the ammonia (signaled by the change from green to purple in the solution containing the ammonia and cabbage juice) compare? How does this comparison match the differences in pH values? What is the basis of any correlation between starting pH values of the two acids and amount required to neutralize the same amount of vinegar solution? Provide explanations for each for the three questions.

Carbonyl bromide, COBr2, decomposes to CO and Br2 with and equilibrium constant of Kc of 0.190 at 73C.
COBr2(g) <--> CO (g) + Br2 (g)
if 0.015 mol COBr2 is in a 2.50 L flask at equilibrium, what are the concentrations of CO and Br2 at equilibrium?

Antifluorite structure (A2B) occurs when anions occupy lattice positions and cations occupy eight tetrahedral lattice sites of f. c. c. One of the best examples which has this structure is Li2O. The ionic radii of Li+ and O2- are as follows : rLi+ = 0.068 nm and rO2- = 0.140 nm. (20 points) a) Draw the antifluorite unit cell of Li2O and show the Li+ and O2- ions in the unit cell. State the equivalent positions of Li+ and O2- ions in the unit cell. How many net ions of each are there in the Li2O unit cell? Why? Provide explanations. How many formula units are there per this unit cell? b) Determine the number of nearest neighbors or the coordination number (C. N.) of each ion in the Li2O unit cell. Provide explanations, if necessary. c) Calculate the ionic packing factor (IPF) of the Lii2O unit cell. d) What are the closed-packed planes in the Li2O unit cell? Express their Miller indices. On this basis, determine the stacking sequence of the Li2O unit cell. (Hint : Use A, B, C for one kind of ion and use , ,  for the other kind)

The corundum (Al2O3) has a rhombohedral Bravais lattice, but it closely approximates a hexagonal lattice and is usually regarded as hexagonal. There are 30 ions per lattice site (and per unit cell). The Al2O3 formula requires that these 30 ions be divided as 12Al3+ and 18 O2-. The Al2O3 structure closely approximates close-packed O2- sheets with two-thirds of the small interstices between sheets filled with Al3+. In other words, close-packed O2- ion containing layers have repeated stacking and the Al3+ ions fill two-thirds of the octahedral interstices between adjacent layers. (22 points) The density of Al2O3 is Al2O3 = 3.8 gram/cm3, Atomic masses are : MAl = 26.98 gram/mol, MO = 16.00 gram/mol Ionic radii are : rAl3+ = 0.05 nm, rO2- = 0.14 nm a) Draw 3 layers/sheets of O2- ions and Al3+ ions in between them. b) Draw the corundum unit cell and show the O2- and Al3+ ions in the unit cell. c) How many Al2O3 molecules are there in 1 cm3 ? How many atoms are there in 1 cm3 of Al2O3? d) How many Al2O3 molecules are there in 1 gram? How many atoms are there in 1 gram of Al2O3? e)Calculate the atomic packing factor of Al2O3

You have a 5.00 g sample of an unknown compound. After analysis you find that its percent composition is 54.5% carbon, 9.10% hydrogen and 36.4% oxygen.

What is the empirical formula for this compound?

If the molar mass of this compound is 132 g/mol, what is its molecular formula?

When you are waiting for the crystals to appear in a recrystallisation experiemnt you should not cool the flask from hot to ice cold because you will cause ......... to happen rather than crystallisation.

1. You have 0.95ft^3 aluminum(density=2700kg/m3,MW=26.98). Calculate the mass in kg, lbm, gmole and lbmole.

2. Assume there are 39 inches in a meter.What is the external surface area in the SI system of a sphere that is 9.0 inches in diameter? Determine the volume in cubic feet. (Note SI system: meters / kg / Newtons etc.)

3. If a US gallon has a volume of 0.134 ft3 and a human mouth has a volume of 0.950 in3, how many mouthfuls of water are required to fill a 7.5 US gallon can?

4. Convert the following:

a) 3.9cm/s to ft/min

b) 187 lbm ft/min2 to kg cm/s2

c) 55 ft3 to gallons

d) 920mg to ounces

e) 2lbm/ft.hr to g/cm.s

5. Water at 4C has a density of 1.0g/cm3 and a molecular weight of 18. What is the density in the following units:

a) kg/m3

b) lbm/ft3

c ) kmol/L

6. Do the following conversions:

a) 1.6 x 10^-2 g cm-1s-1 to lbm ft-1 s-1
b) What is the molecular weight of propionic acid (C2H5COOH).

c) How many kg are there in 10 lb mol of sodium hydroxide (NaOH)

Dissolve 1 mole of Succinic Acid into 1 Liter of water. What is the pH of the solution? What is the molarity of the protonated and depronated forms of Succinic Acid?

calculate the molar volume of hydrogen gas using the newton-raphson method 40 atm and 300 K

R=0.08206 dm³ atm K^-1

for Hydrogen Van der Waals constants a=0.244 dm⁶ atm mol^-2 ,b=0.0266 dm³ mol^-1    

consider the rotation of 50.0mL of a 0.2M HNO3 with 0.10M NaOH calculate the pH of the solution

a) before any extra NaOH has been add
b) after 50mL of NaOH
c) add 100mL of NaOH
d) add 150mL of NaOH

Is Atomic Mass and Atomic Weight the same terms? Or is Atomic mass and Mass Number the same terms?

On the MCAT Kaplan books it says that atomic mass and mass number are the same thing but online and other chemistry textbooks, atomic mass and atomic weight are the same thing.

Can someone please clarify which two terms are the same thing or are they all different? I really need help to make sure I understand this for the MCAT.