A solution is prepared by dissolving 20.2 mL of methanol (CH3OH) in 100.0 mL of water at 25 ∘C. The final volume of the solution is 118 mL. The densities of methanol and water at this temperature are 0.782 g/mL and 1.00 g/mL, respectively. For this solution, calculate each of the following.

Part A
molarity
Express the answer using three significant figures.

Part B

molality

Express the answer using three significant figures.

Part C
percent by mass
Express the answer using three significant figures.

Part D
mole fraction
Express the answer using three significant figures.

why can the citric acid cycle not function without the electron transport chain?

The ammonia/ammonium buffer system is used to optimize polymerase chain reactions (PCR) used in DNA studies. The equilibrium for this buffer can be written as NH4+(aq)??H+(aq)+NH3(aq) Calculate the pH of a buffer that contains 0.045 M ammonium chloride and 0.095 M ammonia. The Ka of ammonium is 5.6×10?10. Express your answer using two decimal places.

boric acid (monoprotic acid of type HA with ka=5.0x10-5) is titrated against .200m naoh(aq)

a) calculate the ph after 20.0ml of .200 m Noah (aq) has been added to 50.0ml of .200m boric acid.

b) calculate the ph at the equivalence point

please show steps thank you

1) a. What is the molar concentration (i.e., molarity) of sucrose (C12H22O11) if 150.0 g is dissolved in 250.0 mL of solution?

b.What is the molar concentration of methanol (CH3OH) if 125.0 mL is dissolved in enough water to make 15.0 L of solution? The density of methanol is 0.792 g/mL.

c.How many grams of NaOH are contained in 250.0 mL of a 0.400 M sodium hydroxide solution?

d.The drinking water standard for lead is 15 ppb (parts per billion). What is this in M? (See Appendix C – Solution Preparation)

e.What volume of 0.650 M sucrose must be diluted with water to prepare 250.0 mL of 0.423 M sucrose? (See Appendix C – Solution Preparation)

f.Which of the following solutions contains the largest concentration of chloride ions: Which contains the largest number of chloride ions? Show work. a. 100 mL of 0.30 M AlCl3 b. 50.0 mL of 0.60 M MgCl2 c. 200.0 mL of 0.40 M NaC

(SHOW WORK, Expaniton) Thank you.

500.0 mL of 0.110 M NaOH is added to 615 mL of 0.200 M weak acid (Ka = 7.63

2. When 1-methylcyclopentane (below) is treated with bromine in the presence of light, two and only two structural isomers are obtained; one is about 90% of the product mixture and the other about 10%. (Ignore sterochemistry for this problem)

a. Draw the major and minor isomers.

b.Provide a complete and detailed mechanism for the formation of the major product. Label each step. Be sure to use proper mechanism arrows!

c. Why are there only two products formed? Explain your answer with a drawing.

Using initial rate, in Chemical Kinetics, what is the missing number in the table? No other information is given. Could you also please explain how you got the answer? I will rate your answer. :D

Thanks in advance.

For the titration of 20.00 mL of 0.100 M Acetic Acid (CH3COOH, Ka = 1.8 � 10-5), calculate the pH after the addition of the following volumes of 0.100 M NaOH.

0.00mL

21.00mL

30.00 mL

Ion Exchange Chromatography

Explain how the Cu²⁺ ions interact with H⁺ ions in the resin.

Explain how the Mg²⁺ ions elute the Cu²⁺ ions from the resin.

18. One mole of CH₄ is burned completely with 20 moles of air.

What is the stack (flue) gas composition?

(Assume air is 21 mole% O₂, 79% N₂)

Somehow the answer to this is (4) but I dont see how that is possible so please EXPLAIN.

Which of the following statements relating to molecular orbital theory (MO) is incorrect?

(1) Combination of two atomic orbitals produces two molecular orbitals

(2) Combination of two 2p orbitals may result in either sigma or pi MOs

(3) A species with a bond order of zero will not be stable.

(4) Molecular orbitals are hybridizations of atomic orbitals.

(5) A diatomic molecule with an odd number of electrons will be paramagnetic

Determine the pH during the titration of 66.6 mL of 0.457 M acetic acid (Ka = 1.8×10-5) by 0.457 M KOH at the following points. (Assume the titration is done at 25 °C.)

a.) Before the addition of any KOH

b.)  After the addition of 16.0 mL of KOH

c.) At the half-equivalence point (the titration midpoint)

d.) At the equivalence point

e.) After the addition of 99.9 mL of KOH

Thank you!!

Quinine (C20H24N2O2) a white crystalline bitter tasting powder which was originally used as a preventative medication for malaria. It is a weak base with kb=3.3 x 10^-6 M. However, Quinine is now more commonly used in small concentrations in tonic water. Quinine is responsible for the fluorescent properties when tonic water is under ultraviolet light (blacklights). Due to the toxic effects of quinine the United States limits the quinine content to 83 ppm for each 1 liter bottle.

Write a balanced chemical equation of quinine solid dissolving in water including all phases, and indicate which species is an acid, base, conjugate acid and conjugate base.

Calculate the pH of the tonic water.