Questions
What is the pH of a solution if I mix together 45 mL of 5.67 mol/L...

What is the pH of a solution if I mix together 45 mL of 5.67 mol/L Acetic acid (CH​ COOH) and 83 mL of 2.35 mol/L NaOH?
Ka of acetic acid = 1.8 x 10

In: Chemistry

How to explain the basic principles, instrument operation and the application of Microwave Induced Plasma -...

How to explain the basic principles, instrument operation and the application of Microwave Induced Plasma - Atomic Emission Spectrometry (MIP-AES)?

In: Chemistry

Ethylene glycol, formula C2H6O2, is used as antifreeze for automobiles and is sometimes mixed with water...

Ethylene glycol, formula C2H6O2, is used as antifreeze for automobiles and is sometimes mixed with water at a 1:1 ratio by volume and produces a solution with a density of 1.07 g/mL. Assume that the solution behaves ideally. Notes: at 25 oC the densities of water and ethylene glycol are 1.00 g/mL and 1.11 g/mL, respectively, the vapor pressures of water and ethylene glycol at 20 oC are 17.54 torr and 0.06 torr, respectively, and Kb and Kf of water are 0.51 K/m and 1.86 K/m, respectively.

a. What is the freezing point of this solution?

b. What is the vapor pressure, in torr, of this solution at 20 oC?

c. What is the osmotic pressure, in atm, of this solution at 25 oC and 0 oC?

d. What is the mass percent (m/m)% of this solution?

In: Chemistry

The ability of an atom in a molecule to pull bonding electrons toward itself is: a)Paramagnetism...

The ability of an atom in a molecule to pull bonding electrons toward itself is:

a)Paramagnetism

b)Diamagnetism

c)Effective nuclear charge

d)Electronegativity

e)Ionization potential

Given the electronegativity values below, select the single bond that is LEAST polar.

Element: H C N O

Electronegativity: 2.1 2.4 3.0 3.5

a) N-H

b) C-H

c) O-N

d) O-C

e) O-H

In: Chemistry

Imagine that you grew a shiny crystal of a brand new compound X. How would you...

Imagine that you grew a shiny crystal of a brand new compound X. How would you determine: (a) the crystal structure of X (b) whether this material is a semiconductor or not

In: Chemistry

Balance the skeleton redox reaction. Write the oxidation state of each compound above the redox symbol,...

Balance the skeleton redox reaction. Write the oxidation state of each compound above the redox symbol, show each redox couple/half reaction. Show both the acidic and basic state. The answer must demonstrate the use of the half reaction method. H5IO6 (aq) + I2 (aq) → IO3 - (aq)

In: Chemistry

A solution is prepared in which 0.00100 mol of Ni(NO3)2 and 0.500 mole of NH3 are...

A solution is prepared in which 0.00100 mol of Ni(NO3)2 and 0.500 mole of NH3 are dissolved in a total volume of 1.00 L. What is the concentration of Ni(H2O)62+ ions in the solution at equilibrium?

In: Chemistry

A 2.800×10−2 M solution of NaCl in water is at 20.0∘C. The sample was created by...

A 2.800×10−2 M solution of NaCl in water is at 20.0∘C. The sample was created by dissolving a sample of NaCl in water and then bringing the volume up to 1.000 L. It was determined that the volume of water needed to do this was 999.2 mL . The density of water at 20.0∘C is 0.9982 g/mL.

1a) Calculate the molality of the salt solution. Express your answer to four significant figures and include the appropriate units.

1b) Calculate the mole fraction of salt in this solution. Express the mole fraction to four significant figures.

1c) Calculate the concentration of the salt solution in percent by mass. Express your answer to four significant figures and include the appropriate units.

1d) Calculate the concentration of the salt solution in parts per million. Express your answer as an integer to four significant figures and include the appropriate units.

In: Chemistry

For each of the substances in below classify it as a strong or weak electrolyte and...

For each of the substances in below classify it as a strong or weak electrolyte and state whether it exists in solution as molecules, ions, or a mixture of both molecules and ions.

a) hypochlorous acid

      b) strontium hydroxide

      c) perchloric acid

      d) butanoic acid

In: Chemistry

The thermal decomposition of dimethyl ether CH 3 2 O g CH 4 g H 2...

The thermal decomposition of dimethyl ether CH 3 2 O g CH 4 g H 2 g CO g is to be carried out in an isothermal 2.00-liter laboratory reactor at 600°C. The reactor is charged with pure dimethyl ether at a pressure of 350 torr. After about two hours, the reactor pressure is 875 torr. (a) Has the reaction proceeded to completion at the end of the two-hour period? If not, what percentage of the dimethyl ether has decomposed? (b) Taking elemental species [C(s), H2(g), O2(g)] at 25°C as references, prepare and fill in an inlet-outlet enthalpy table. (See Example 9.5-2.) Use tabulated data for methane, hydrogen, and carbon monoxide, and the following data for dimethyl ether: Δ H f 180.16 kJ mol C p J mol K 26.86 0.1659 T 4.179 10 5 T 2 T in kelvins (c) Calculate Δ H r 600 C and Δ U r 600 C for the dimethyl ether decomposition reaction. (d) How much heat (kJ) was transferred to or from the reactor (state which it is) during the two-hour period of the reaction? (e) Suppose the reaction were instead carried out in an expandable reactor at 600°C at a constant pressure of 350 torr, with the same final percentage decomposition of dimethyl ether. Calculate the final volume of the reactor and the required amount of heat transfer. (Note: These should both be quick calculations.) Explain why the values of Q calculated in Part d and in this part are different, even though the initial conditions and extents of reaction are the same.

In: Chemistry

Make 350 mL of 43 mM sodium phosphate buffer, pH 7.0 without titrating with NaOH or...

Make 350 mL of 43 mM sodium phosphate buffer, pH 7.0 without titrating with NaOH or HCI. Show your calculations, which 2 species of sodium phosphate you choose (species are H3PO4, NaH2PO4, Na2HPO4, and Na3PO4; dissociation pKa’s are 2.16, 7.21, and 12.32), and how much of each you weighed out. Check and read your final pH.

In: Chemistry

A 0.120 M solution of an enantiomerically pure chiral compound D has an observed rotation of...

A 0.120 M solution of an enantiomerically pure chiral compound D has an observed rotation of 0.24° in a 1-dm sample container. The molar mass of the compound is 140.0 g/mol.

a) what is the specific rotation of D?

b) what is the observed rotation if this solution is mixed with an equal volume that is 0.15 M in L, L is the enantiomer of D?

c) what is the observed rotation if the solution of D is diluted with an equal volume of solvent?

d) what is the specific rotation of D after the diltuion descibed in part (C)?

e) what is the specific rotation of L, the enantiomer of D, after the dilution described in part C?

f) what is the observed rotation of 100 ml of a solution that contains 0.01 mole of D and 0.005 mole of L? Assume a 1 dm path length

In: Chemistry

Cocaine is a weak organic base whose molecular formula is C​17H​ ​21N​ O​4.​ At 15 degrees​C...

  1. Cocaine is a weak organic base whose molecular formula is C​17H​ ​21N​ O​4.​ At 15 degrees​C an aqueous solution of cocaine was found to have a pH of 8.53 and an osmotic pressure of 52.7 torr.

    a) What is the molarity of this solution? b)What is kb of cocaine? c)What concentration of NaOH solution would have the same pH as this solution of

In: Chemistry

The table of diprotic acids below shows how the acidity of the 1st proton is always...

The table of diprotic acids below shows how the acidity of the 1st proton is always much higher than the acidity of the second proton.Thus, the pH of the solution is dominated by the equilibrium for the loss of the 1st proton.

Compound Ka1 Ka2
H2CO3 4.3 X 10-7 5.6 X10-11
H2S 8.9 X 10-8 1.0 X 10-19
H2Te 2.3 X 10-3 1.6 X 10-11
H2SO3 1.7 X 10-2 6.4 X 10-8

What is the pH for a 1.12 M solution of Li2S?

In: Chemistry

Drops are used as a measure of volume in this lab.  Explain why it is important to...

Drops are used as a measure of volume in this lab.  Explain why it is important to beconsistent in the size and counting of the drops.

In: Chemistry