Quinine, C20H24N2O2, occurs naturally in the bark of the cinchona tree and was the first effective...

Quinine, C20H24N2O2, occurs naturally in the bark of the cinchona tree and was the first effective treatment for malaria. It is a diprotic base with Kb values of (the acidic protons are shown in red) C20H24N2O2 + H2O HC20H24N2O2+ + OH- Kb2 = 1.0 × 10-6 HC20H24N2O2+ + H2O H2C20H24N2O22+ + OH- Kb1 = 1.58 × 10-10

a) The recommended IV dose of quinine is 0.800 g/kg, that is, 0.800 g of quinine per 1 kg of water. If we assume that the density of the solution is 1.00 g/mL, what is the pH of this solution? The molar mass of quinine is 324.412 g/mol. For simplicity, abbreviate C20H24N2O2 as Q.

b) 100 mL of the solution from part a is then titrated with a solution of 0.010 M HCl. How many mL of HCl solution is required to reach the first equivalence point?

c) What is the pH at the first equivalence point?

d) What is the pH when 32.00 mL of HCl has been added?

e) What is the pH at the second equivalence point?

f) Quantitatively draw the resulting titration curve on the axes below. Be sure to label both axes, equivalence points and buffer regions. Be as accurate as use can and make use of your results for parts a-e. g) The pH in the stomach is often quite low, between 2 and 3. What species of quinine is predominant at a pH of 2.5?

h) The pH of blood is buffered at 7.4. What species of quinine is predominant at this pH?

Solutions

Expert Solution

queen_honey_blossom answered 1 year ago

Next > < Previous

Related Solutions

Quinine occurs naturally in the bark of the cinchona tree. For centuries, it was the only...

Quinine occurs naturally in the bark of the cinchona tree. For centuries, it was the only treatment for malaria. Quinine contains two weakly basic nitrogen atoms, with Kb1=3.31 x 10^-6 and Kb2=.00000000135 at 25 C. Calculate the pH of a .011 M solution of quinine in water.

Quinine is a natural product extracted from the bark of the cinchona tree, which is native...

Quinine is a natural product extracted from the bark of the cinchona tree, which is native to South America. Quinine is used as an antimalarial agent. When 3.10 g of quinine is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 7.95 °C. The freezing point and Kf constant for cyclohexane can be found here. Calculate the molar mass of quinine. https://sites.google.com/site/chempendix/colligative

Quinine, an alkaloid derived from a tree that grows in tropical rain forests, is used in...

Quinine, an alkaloid derived from a tree that grows in tropical rain forests, is used in the treatment of malaria. Like all alkaloids, quinine is a sparingly soluble weak base: 1.00 g of quinine will dissolve in 1.90 × 102 L of water. What is the pH of a saturated solution of quinine? The number of significant digits is set to 2; the tolerance is +/-4% A 27.4 mL sample of saturated quinine is titrated with 0.00843 M HCl solution....

33) A beaver eats the inner bark of an aspen tree and converts the potential energy...

33) A beaver eats the inner bark of an aspen tree and converts the potential energy in this bark into the kinetic energy of building a lodge (in the form of a river dam) complete with an underwater entrance! This example illustrates: A) How energy can be destroyed and created B) That all energy transformations lead to an increase in local disorder C) How every energy transformation decreases the entropy of the universe D) That beavers are energy transformers E)...

Nitric oxide (NO) occurs in the atmosphere naturally at a concentration of 0.1ppb. determine whether or...

Nitric oxide (NO) occurs in the atmosphere naturally at a concentration of 0.1ppb. determine whether or not this concentration represents e equilibrum with respect to H2o,O2 and NH3(amonia), all in the gasous phase. a)Covert the concentration of NO to its partial pressure, assuming an atmospheric pressure of 1 bar. b)calculate the partial pressure of NH3 if the system uis controlled by chemical equilibrum.

Replication is a process that occurs naturally in a cell, where PCR is done by scientists...

Replication is a process that occurs naturally in a cell, where PCR is done by scientists in a laboratory. Compare replication and PCR by discussing the components and processes that are similar and the components and processes that are different. Finally, tell me why PCR is important in RFLP analysis.

Consider the following hypothetical scenario: Mary has been using the bark from the weeping willow tree...

Consider the following hypothetical scenario: Mary has been using the bark from the weeping willow tree in her garden for many years to treat aches and pains. When she was very young, she had heard from someone that willow bark could be a useful anti-inflammatory and decided to experiment with the bark herself. Over many years, she came up with a method of steeping the bark to produce a tea that tastes good, and in her view, is very effective....

Beech Bark Disease is a (mostly) fungal disease that was first observed in the US in...

Beech Bark Disease is a (mostly) fungal disease that was first observed in the US in NYC in the 1950's and is spreading south. It kills mature trees in as little as 5 years. As it spreads through the UGA Botanical Garden, the size of the beech population is reduced by 98%, leaving only the 2% of individuals that exhibit some resistance to the fungus. Over time the population increases to its original size. All of the individuals in the...

Hypothetical tree species "x" regenerates naturally, completely and quickly on a heavily disturbed site - that's...

Hypothetical tree species "x" regenerates naturally, completely and quickly on a heavily disturbed site - that's just what it does well as an early-seral species. What factors will then regulate its development as it progresses (or tries to progress) through time as well as the stages of stand dynamics?

Unfortunately, arsenic occurs naturally in some ground water†. A mean arsenic level of μ = 8.0...

Unfortunately, arsenic occurs naturally in some ground water†. A mean arsenic level of μ = 8.0 parts per billion (ppb) is considered safe for agricultural use. A well in Texas is used to water cotton crops. This well is tested on a regular basis for arsenic. A random sample of 31 tests gave a sample mean of x = 6.8 ppb arsenic, with s = 2.6 ppb. Does this information indicate that the mean level of arsenic in this well...

Subjects