A 0.380 m aqueous solution of NaCl is prepared at 20.0∘C. Assume that the density of the solution at 20.0∘C is 1.082 g/mL.

Calculate the molarity of the salt solution.

Describe why high pressures but low temperatures cause substances to deviate from ideal gas conditions. Make sure to discuss the assumptions we made to come to the ideal gas law and how high pressures and low temperatures negate those assumptions.

Using electronegativity arguments, classify the following diatomic molecules as nonpolar (N), polar (P), or ionic (I).

NaF

GaAs

H2

RbO

CO

for a linear molecule of polyethelyne of molar mass 11980 g mole ^- calculate :

The contour length of the molecule

B) the end to end distance in thr fully extended molecule and

C) the root mean square end to end distance according to the valence angle model .

In the calculation, end group can be neglected and it may be assumed that the c-c bonds are of length 0.154 nm your reasoning, which of the very large number of possible conformations of the molecyle is the most stable

Calculate the pH for each of the following cases in the titration of 50.0 mL of 0.170 M HClO(aq) with 0.170 M KOH(aq).

(a) before addition of any KOH

(b) after addition of 25.0 mL of KOH

(c) after addition of 30.0 mL of KOH

(d) after addition of 50.0 mL of KOH

(e) after addition of 60.0 mL of KOH

Match each element with the full ground-state electron configuration of the monatomic ion it is most likely to form. (Enter the 6 correct letters, in order: BABCEG, FBAGCC, etc.).

1) K A. 1s22s22p63s23p64s1

2) Cl B. 1s22s22p6

3) Na C. 1s22s22p63s23p64s23d104p65s1

4) Al D. 1s22s22p63s23p1

5) N E. 1s22s22p63s23p6

6) Rb F. 1s2

G. 1s22s22p63s23p64s23d104p6

please show the answer in steps.

1)What is the change in entropy when a) 100 g of ice is melted at 0 ℃ b) 100 g of water is vaporized to 100 ℃

Use the values for each step to calculate the change in entropy when 100 g of ice at 0 ℃ is transformed to water vapor at 100 at ℃ . Suppose that the changes are brought about by a heater that supplies at a constant rate and sketch a graph showing a) the change in temperature of the system b) the enthalpy of the system, c) the entropy of the system as a function of time.

2)The average of the enthalpy of vaporization of propanone, C₃H₆O over the temperature range of 280 to 340 K is 30.2 kJ/mol. The vapor pressure is 30.600 kPa at 298.15 K. Estimate the normal boiling temperature of propanone.

How many liters of methanol would be required daily to remove the nitrogen from a 200,000-L/day sewage treatment plant producing an effluent containing 50 mg/L of nitrogen? Assume that the nitrogen has been converted to NO3- in the plant. The density of CH3OH is 0.791 kg/L.

The denitrifying reaction is: 6 NO3- + 5 CH3OH + 6 H+ (Denitrifying bacteria) → 3 N2(g) + 5 CO2 + 13 H2O

Suppose we titrate 20.0 mL of 0.20 M of formic acid (HCHO2, Ka= 1.8 x 10^-4) with 0.20 M KOH. Calculate the pH for the following:

a) before any base is added

b) when half of the formic acid has been neutralized

c) after a total of 15 mL has been added

d) at the equivalence point

Some people have an allergic reaction to the food preservative sulfite (SO32−). Sulfite in wine was measured by the following procedure: To 50.0 mL of wine were added 5.00 mL of solution containing (0.8043 g KIO3 + 5 g KI)/100 mL. Acidification with 1.0 mL of 6.0 M H2SO4 quantitatively converted IO3− into I3−. The I3− reacted with SO32− to generate SO42−, leaving excess I3− in solution. The excess I3− required 12.86 mL of 0.04818 M Na2S2O3 to reach a starch end point. Find the concentration of sulfite in the wine. Express your answer in mol/L and in mg SO32− per liter.

1. a)Which of the following statements are TRUE for a buffer solution.
Select all that are True.
_ A buffer can be prepared by combining a weak acid and its conjugate base."
_ A buffer resists changes in pH.
_ When a strong acid is added to a buffer, it reacts with the conjugate base which slightly increases the pH of the solution.

3. Given the following data set: Indicate where the buffere capacity has been exceeded.

The buffer capacity was exceeded when_______mL of NaOH was added?

why does the measurement of fluorescence data require a more intense source of uv/visible spectroscopy? specific. b) what is the typical source for spectofluorometer? c) for the photomuiltiplier transducer what is the mode off operation used signal to noise?

How to convert 100 micrograms per milliliter to 10 nanomolar?

Starting from a symbolic expression of the Second Law of Thermodynamics, show how arguments based purely upon considerations of entropy lead to the formalism which we call Gibbs

A 0.1936 gram sample of primary standard K2Cr2O7 was dissolved in water, the solution was acidified, and after the addition of KI, the titration of liberated I2 required 33.61 ml of Na2S2O3 solution. Calculate the molarity of the thiosulfate solution.