What are the differences between MRI spectra of body tissue against that of an organic compounds ?

Consider the reaction of nitrous acid in water where Ka = 4.0 ✕ 10−4. HNO2(aq) + H2O(l) equilibrium reaction arrow NO2−(aq) + H3O+(aq) (a) Which two bases are competing for the proton? (Select all that apply.) HNO2 H2O NO2− H3O+ (b) Which is the stronger base? HNO2 H2O NO2− H3O+ (c) In light of your answer to (b), why do we classify the nitrite ion (NO2−) as a weak base? The nitrite ion is a (stronger or weaker) base than water and produces (acidic or basic) solutions in water. When the nitrite ion is put into solution as the only major species, the competition is between the nitrite ion and the hydroxide ion for the proton. The resulting equilibrium lies far to the left producing a Kb value of (greater than, less than, or equal to) one. (Hydronium, hydroxide, nitrite, or nitrous acid) is the strongest base possible in water. Species that are classified as weak bases are stronger bases than water but are weaker bases than(Hydronium, hydroxide, nitrite, or nitrous acid) . Use an appropriate reaction to justify your answer. (Include states-of-matter at 25°C and 1 atm in your answer.)

6. Sometimes it's hard to tell which thing is the solvent and which the solute – for example you can make mixtures of water and methanol at any proportion. Fortunately, Raoult's law doesn't care which thing you call the solvent or solute; at a given temperature, both things have vapor pressures that fit the equation    P_A = Χ_A P_A⁰ - where the right-hand side of the equation is the mole fraction times the pure liquid vapor pressure at that temperature.

a.) Calculate the vapor pressures for methanol (CH₃OH, 32.04 g/mol, P⁰ = 13.02 kPa) and water (18.02 g/mol, P⁰ = 3.20 kPa) above a mixture containing one mole each of methanol and water (in a sealed container with a head-space for the vapor).

b.) Which of the two components' (methanol's or water's) vapor pressure would be depressed the most by addition of 10 g of NaCl (58.44 g/mol) assuming complete dissolution by a mechanism similar to that which takes place in aqueous solution (similar IMFs)? Calculate the percent change in that component's vapor pressure.

Determine the pH of each of the following solutions., 3.6×10−2 M HI,9.23×10−2 M HClO4, a solution that is 4.0×10−2 M in HClO4 and 4.8×10−2 M in HCl, a solution that is 1.01% HCl by mass (Assume a density of 1.01 g/mL for the solution.)

please show work

What were some error's in Millikan's oil drop experiment and what were their sources. This deals with his finding charge of electron experiment .

Discuss proper operation and maintenance of glass pH electrodes.

A solution containing a mixture of the compounds X and Y had an absorbance of 1.00 at 443 nm and an absorbance of 0.861 at 520 nm when measured with a 1.00 cm cell. The molar absorptivities (ε) of X and Y at each wavelength are shown in the table below. 443 16410 3871. 520 3993 6425

A chemist at a pharmaceutical company is measuring equilibrium constants for reactions in which drug candidate molecules bind to a protein involved in cancer. The drug molecules bind the protein in a 1:1 ratio to form a drug-protein complex. The protein concentration in aqueous solution at 25 ∘C is 1.78×10−6 M . Drug A is introduced into the protein solution at an initial concentration of 2.00×10−6M. Drug B is introduced into a separate, identical protein solution at an initial concentration of 2.00×10−6M. At equilibrium, the drug A-protein solution has an A-protein complex concentration of 1.00×10−6M, and the drug B solution has a B-protein complex concentration of 1.40×10−6M.

A substitutional solid solution is formed between silver and gold. Calculate the weight percent of gold that should be added to silver to obtain an alloy with 5.5 x 1021 gold atoms per cm3 . Pure gold and silver have densities of 19.32 and 10.49 g/cm3 , respectively

(a) Do you expect the surface energy to be greater than, the same as, or less than the grain boundary energy, why? (b) A small angle grain boundary has a less grain boundary energy than a high-angle one. Why?

Consider the titration of 10.00 mL of 0.10 M acetic acid (CH3COOH) with 0.10 M NaOH

a. What salt is formed during this reaction?

b. do you expect the salt solution at the equivalence point to be acidic, neutral, or basic?

Calculate the pH of this solution at the equicalence point.

Which of the following actions will cause the equilibrium to shift such that the partial pressure of NO gas will increase?

2NO(g) + O2(g) ⇌ 2NO2(g)  ΔH = −13.1 kJ

Increase the pO2(g)

Increase the volume

Decrease the pNO2(g)

Write the balance molecular and net ionic equations for the following meathesis reactions, if they occus.

a. barium nitrate + sodium carbonate

b. lead(II) nitrate + sodium carbonate

c. zinc acetate + sodium carbonate

d. barium nitrate + sodium sulfate

e. lead(II) nitrate + sodium sulfate

f. zinc acetate + sodium sulfate

g. barium nitrate + potassium iodide

h. lead(II) nitrate + potassium iodide

i. zinc acetate + potassium iodide

Use the data below from an electron impact mass spectrum of a pure compound to deduce its structure. Draw your structure in the drawing window.

1.

2.

3.

Thanks