Chapter is over Equilibrium Chemistry and connecting to Gravimetric systematic solving.

6. Write a charge balance equation and mass balance equations for the following solutions. Some solutions may have more than one mass balance

Please help I don't understand how to derive these.

a. 0.1 M NaCL

b. 0.1 M HCl

c. 0.1 M HF

g. 0.10 M HCl and 0.05 M NaNO2

84) You are in charge of quality control at an automotive manufacturing facility that is using UNS 7068 aluminum alloy for the engine blocks.   How can you verify that this is in fact UNS 7068. Be specific in providing the measurements whatever technique you propose should read for the authentic alloy ?

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Please answer in clear words NO guessing!!! Thanks

Q: Please explain your interest in participating in the LifeSci NYC internship program. How does this program fit in your future career goals? What professional and personal skills do you hope to learn during this internship? Note that this program welcomes both scientists and non-scientists; either way, we want to hear about your interest in being a part of the life sciences industry in New York City. (Up to 500 words) *

Help me with some ideas, thank you!

The decomposition of XYXY is second order in XYXY and has a rate constant of 7.16×10⁻³ M−1⋅s−1M−1⋅s−1 at a certain temperature.

a) What is the half-life for this reaction at an initial concentration of 0.100 MM?
b)

How long will it take for the concentration of XYXY to decrease to 12.5%% of its initial concentration when the initial concentration is 0.100 MM?
c) How long will it take for the concentration of XYXY to decrease to 12.5% of its initial concentration when the initial concentration is 0.200 MM?
d) If the initial concentration of XYXY is 0.140 MM, how long will it take for the concentration to decrease to 6.00×10⁻² MM?
e)

If the initial concentration of XYXY is 0.050 MM, what is the concentration of XYXY after 45.0 ss?
f)

If the initial concentration of XYXY is 0.050 MM, what is the concentration of XYXY after 600 ss?

Describe the process of each step in the experiment (Fischer esterification/ Isopentyl acetate lab).

a. The reaction is done using a reflux condenser.

b. The reaction mixture is washed with water.

c. The reaction mixture is washed with aqueous sodium bicarbonate.

d. Anhydrous sodium sulfate is added to the top layer.

e. The final product is purified by distillation.

Carbenes are neutral species, which contain a carbon with six valence electrons.
(i) Draw the hybrid structure of a singlet carbene. In your drawing, identify the
HOMO and LUMO molecular orbitals.
(ii) Draw the reaction of a singlet carbene with an alkene, and explain why this
occurs via a side-on approach. (In your answer, consider both the HOMO and
LUMO of the alkene)

Reaction 1: NaOH(s)--> NaOH (aq)

Reaction 2: NaOH(s) + HCl (aq)--> NaCl(aq)+H2O(l)

Reaction 3: NaOH(aq) +HCl (aq) --> NaCl (aq) + H2O (L)

1) Describe each reaction as endothermic or exothermic and explain your reasoning.

2) Examine the chemical equations for the three reactions. Determine their relationship in a way that is consistent with Hess's Law. (i.e. verify that Hess's Law is upheld. Reaction 3 is the target equation).

3) Why is heat a stoichiometric quality?

4) Just what IS a heat of solution?

At a temperature of 25ºC the following cell shows a potential of 0.7585 V: Cd/CdCl2 (0.01 M) II AgCl (sat)/Ag

(i) calculate the standard electromotive force of the cell; (ii) Calculate the mean activity coefficients in the CdCl2 solution.

At a temperature of 25ºC the following cell shows a potential of 0.7585 V: Cd/CdCl2 (0.01 M) II AgCl (sat)/Ag (i) calculate the standard electromotive force of the cell; (ii) Calculate the mean activity coefficients in the CdCl2 solution.

Given the mole of air as 9.2x10^-5 mol, the volume of water vapor, after correction, is 5.0 mL while the temperature is 75 ^oC, what is the vapor pressure of water in mmHg if the atmospheric pressure (P_atm ) is 0.989 atm.

Explain why it is necessary to select only one wavelength to pass through the sample (i.e. why don’t we just shine white light into the sample and measure the amount of light that passes through?)

In this part of today's experiment you will produce cyanotypes using watercolor paper. Directions 1. Each student should obtain a piece of 4” x 5” watercolor paper. Work with ONE partner. 2. Each pair should prepare the following solution in a 250 mL beaker. 1.2g ferric ammonium citrate 0.6g potassium ferricyanide 20 mL of water 3. Stir until dissolved and describe the color of the mixed solution. ______________________ 4. Place the paper in one of the plastic trays under the hood. Using a flat foam brush, coat one side completely with the solution. Wipe first in one direction and then a second time at a right angle to the first direction. 5. CAREFULLY dry the paper using a hot air gun, or place in the oven in the Prep room. 6. When dry, print the dry paper by clipping a large negative image on top of the paper and exposing it to sunlight (outside, if it’s sunny) or a UV light source (inside). 7. When the exposed regions of the paper are changed in color to a deep blue-green, unclip and remove the negative. 8. Wash the paper with a gentle stream of tap water to remove the soluble unreacted light sensitive chemicals. 9. Dry the blueprints with a hot air gun, or in the oven in the Prep room.

Discussion Questions

1. What develops the image?

2. What works as the fixer for the image?

3. Write balanced chemical equations for the reactions observed.

Just as pHpH is the negative logarithm of [H3O+][H3O+], pKapKa is the negative logarithm of KaKa

pKa=−logKapKa=−log⁡Ka

The Henderson-Hasselbalch equation is used to calculate the pHpH of buffer solutions:

pH=pKa+log[base][acid]pH=pKa+log⁡[base][acid]

Notice that the pHpH of a buffer has a value close to the pKapKa of the acid, differing only by the logarithm of the concentration ratio [base]/[acid][base]/[acid]. The Henderson-Hasselbalch equation in terms of pOH and pKbpKb is similar.

pOH=pKb+log[acid][base]

How many grams of dry NH4ClNH4Cl need to be added to 1.80 LL of a 0.100 MM solution of ammonia, NH3NH3, to prepare a buffer solution that has a pHpH of 8.85? KbKb 1.8×10−51.8×10−5.

Express your answer with the appropriate units.

Calculate the theoretical yield of aspirin a) in moles and b) in grams. Assume use of 1.0 g salicylic acid and 2.5 mL acetic anhydride. Show all calculations.

Which plastic types gives identical infrared spectra? Why does this make sense from their structures?

Background info: This is referring to the 6 plastic types: PETE, HDPE, LDPD. PVP, PP ad PS.