General organic chemistry Questions and Answers
Organic Chemistry
General organic chemistryAn organism uses the following reaction to generate free energy:
CH4 + SO4 2- + 2H+ -> H2S + CO2 + 2H2O
which of the following would increase the amount of free energy available to this organism?
There is more than one correct answer, select all that apply to receive credit.
The H₂S concentration were to go down.
The CH4 concentration were to increase.
The SO42 were to decrease
The pH were to decrease
The CH4 concentration were to decrease
The CO₂ were to increase
Organic Chemistry
General organic chemistryWhen para-bromotoluene is treated with sodium amide two products are obtained. For the mechanism, draw the curved arrows as needed. Include lone pairs and charges in your answer. Do not draw out any hydrogen explicitly in your products. Do not use abbreviations such as Me or Ph.
Organic Chemistry
General organic chemistryWhich of the test metals in experiment 5 exhibited the greatest reactivity towards H₂O?
Ca
Al
Mg
Organic Chemistry
General organic chemistry(2) Find the AH for the reaction below, given the following reactions and subsequent ΔH values:
2CO2(g) + H2O(g) → C2H2(g) + 5/2O2(g)
C2H2(g) + 2H2(g) → C2H6(g) ΔH =-94.5 kJ
H2O(g) --> H2(g) + 1/2O2 (g) ΔH =71.2 kJ
C2H6(g) + 7/2O2(g) → 2CO2(g) + 3H2O(g) ΔH =-283 kJ
answer= 235 kJ
Organic Chemistry
General organic chemistryWhen the following equation is balanced using the smallest possible integers, what is the number in front of the substance in bold type?
Pb(NO3)2 + K2CO3 --> PbCO3 + KNO3
5
4
3
2
1
Organic Chemistry
General organic chemistry9. Build a model of CH₂BrCI. Next, build a model of the mirror image of your first molecule. How are these models related?
10. Build a model of CHBrCIF. Next, build of model of the mirror image of your first molecule. How are these molecules related?
Organic Chemistry
General organic chemistryOne of the radioactive isotopes used in medical treatment or analysis is palladium-103. The half-life of palladium-103 is 17 days. How many days is/are required for the activity of a sample of palladium-103 to fall to 12.5 percent of its original value?
Organic Chemistry
General organic chemistryWrite the formula for (R)-3-chlorocyclohexene
a. Using wedges and broken lines
b. Haworth projection
c. Upload picture of the model in each one of the projections
Organic Chemistry
General organic chemistryWhich of the following is the best definition of a pair of atropisomers?
a. A pair of enantiomers which do not interconvert.
b. A pair of enantiomers which lack chiral centers.
c. A pair of enantiomeric structures which lack chiral centers and interconvert by rotation around, carbon-carbon single bonds.
d. A pair of enantiomers which lack chiral centers and do not interconvert because of hindered rotation around carbon-carbon single bonds.
Organic Chemistry
General organic chemistrySuppose you did NOT swirl the container properly to get rid of all the CO₂ gas during the titration, and ended up with leftover CO₂ still in the container when you obtained the stable green color (indicating complete neutralization).
(b) Using at least TWO complete sentences: Would doing this OVERESTIMATE or UNDERESTIMATE the MOLES of acetic acid left over after the H₂-producing ("First steps") reaction was complete? What is the chemical (and/or mathematical) explanation for why this is?
Organic Chemistry
General organic chemistryUse the dissociation reaction to answer the question.
FeSCN2+ (aq) = Fe3+ (aq) + SCN- (aq)
In the reaction, FeSCN2+ ions are red, Fe3+ ions are pale yellow, and SCN- ions are colorless.
A solution at equilibrium is yellow-orange. The concentration of SCN- ions is increased by a moderate amount. Which color will the solution most likely become?
colorless
orange
red
yellow
Organic Chemistry
General organic chemistry5.54 The specific rotation of (S)-carvone (at 20°C) is +61. A chemist prepared a mixture of (R)-carvone and its enantiomer, and this mixture had a specific rotation of -55.
(a) What is the specific rotation of (R)-carvone at 20°C?
(b) Calculate the % ee of this mixture.
(c) What percentage of the mixture is (S)-carvone?
Organic Chemistry
General organic chemistry1 mol Al₂(CrO4)3 = 401.96 g Al₂(CrO4)3
6. Na.N
1 mol Na₂N = 82.98 g Na₂N
7. NH,Br
1 mol NH₂Br = 97.95 g NH,Br
8. H.S04
1 mol H₂SO3(aq) = 82.09 g H₂SO3 (aq)
9. Ba(CIO),
1 mol Ba(CIO₂)₂ = 336.23 g Ba(CIO₂)₂
Organic Chemistry
General organic chemistryThe reaction is pH dependent even though the H+ ion does not appear in the overall reaction. Which of the following explains this observation?
Check all that apply.
The exponent of [H+] in the rate law is zero.
H+ serves as a catalyst in the reaction.
H+ enters the reaction mechanism after the rate-determining step.
H+ is an intermediate in the reaction mechanism.
Organic Chemistry
General organic chemistryWhat are the partial pressures in a mixture contaiin 0.254 mol of O2 and 0.569 mol of N2 if the total pressure is 157.0 torr?
PO2 = 48.5 torr; PN2 = 109 torr
PO2 = 70.1 torr; PN2 = 86.9 torr
PO2 = 39.9 torr; PN2 = 89.3 torr
PO2 = 76.9 torr; PN2 = 80.1 torr
Organic Chemistry
General organic chemistryThe amount of energy needed to heat 2.00 g of carbon from 50.0°C to 80.0°C is 42.60 J. The specific heat capacity of this sample of carbon is
2556 J/g °C
0.710 J/g °C
1278 J/g °C
1.41 J/g °C
0.266 J/g °C
Organic Chemistry
General organic chemistryA reaction occurs in a calorimeter, resulting in the starting and final temperatures shown below. What can you say about the reaction and the enthalpy change (AH) during the reaction?
Starting temperature: 21.0 °C
The reaction is endothermic and AH is positive.
The reaction is endothermic and AH is negative.
The reaction is exothermic and AH is negative.
The reaction is exothermic and AH is positive.
Organic Chemistry
General organic chemistryWhich statement describes condensation polymers?
They are made of monomers that have two functional groups
They may form between an organic acid and an amine
When they are produced, a small molecule (such as water, ammonia, or ethanol) is also produced
They may contain an ester bond or an amide bond
Organic Chemistry
General organic chemistrya. Write the formulas condensed (CH3CH2 etc.) and line for the branches that have common names.
b. Write the common and IUPAC names for each one e.g isopropyl = (1-methylethyl).
Organic Chemistry
General organic chemistryA chemistry teacher adds red food coloring to water and students observed the dye spreading out to fill the container. Is the teacher demonstrating a physical or chemical change?
Chemical change because a new substance was formed.
Physical change because red dye mixed with the water.
Physical change because a new substance was formed.
Chemical change because red dye reacted with the water.
Organic Chemistry
General organic chemistryDiethyl ether is made from ethanol. The reaction is given below.
2C2H5OH → (C2H5 )2O + H₂O Ethanol
Diethyl ether
In an experiment, 517 g of ethanol gave 391 g of diethyl ether. What was the percent yield in this
experiment?
Organic Chemistry
General organic chemistryDraw both chair conformations for each of the following compounds. In each case, identify the more stable chair conformation:
(a) Methylcyclohexane
(b) trans-1,2-Diisopropylcyclohexane
(c) cis-1,3-Diisopropylcyclohexane
(d) trans-1,4-Diisopropylcyclohexane
Organic Chemistry
General organic chemistryHydrogenation of 3-nonyne using Lindlar's catalyst can be described as
(a) a regioselective reaction
(b) a regioselective and a stereoselective reaction
(c) an electrophilic substitution reaction
(d) forming a product of formula C9H18
(e) an oxidation reaction
Organic Chemistry
General organic chemistryChoose the incorrect statement.
Aniline is produced by Hoffmann degradation of benzamide.
Butanamide gives propanamine by Hoffmann bromamide reaction.
Gabriel synthesis is used for preparation of aniline
Amide on reduction with LiAIH4 yield amines.
Organic Chemistry
General organic chemistryDetermine whether 1-chloro-2-methylbutane contains a chiral center. How many different substituents do you count at atom #(2)?
Organic Chemistry
General organic chemistrya. Draw the orbital sketch for methanal (formaldehyde) HCOH. Indicate the hybridization of the atomic orbitals. Label each orbital. Label the molecular orbitals as sigma and or pi Label the angles
b. Build the model
c. Upload the picture of the model with the sketch
Organic Chemistry
General organic chemistryWhich of the following statements is not true regarding SN2 reactions?
The alkyl halide and nucleophile are both present in the transition state of an SN2 reaction.
If the alkyl halide is chiral, the stereochemistry will be scrambled during the SN2 reaction.
SN2 reactions work best with aprotic solvents.
SN2 reactions are fastest with primary alkyl halides.
Organic Chemistry
General organic chemistryDoes a reaction occur when aqueous solutions of magnesium nitrate and zinc sulfate are combined?
yes
no
If a reaction does occur, write the net ionic equation.
Organic Chemistry
General organic chemistryWhich of the following approaches would represent a high-yielding synthesis of 4-chloroheptane (without the formation of byproducts)?
(a) reaction of HCI with cis-3-heptene
(b) reaction of HCI with 3-heptyne
(c) reaction of HCI with trans-3-heptene
(d) reaction of 3-heptanol with SOCI₂
(e) none of (a), (b), (c) or (d)
Organic Chemistry
General organic chemistryStatementI: In bleaching powder oxidation state of Ca is +2. Statement II: In bleaching power, chlorine is present in both +1 and -1 oxidation states. Which of the following statement(s) is/are correct?
Both statements are correct
Both statements are incorrect
Statement I is correct but statement II is incorrect
Statement I is incorrect but statement II is correct
Organic Chemistry
General organic chemistryConsider the reaction between benzoic acid and aqueous sodium hydroxide. Which H is lost by the acid?
the CO₂H H atom
one of the five ring H atoms
Organic Chemistry
General organic chemistryDraw any diastereomer of (2R,3R)-2,3-dichloropentane. Be careful to indicate proper stereochemistry. Draw the molecule on the canvas by choosing buttons from the Tools (for bonds), Atoms, and Advanced Template toolbars. The single bond is active by default. Show the appropriate stereochemistry by choosing the dashed or wedged buttons and then clicking a bond on the canvas.
Organic Chemistry
General organic chemistrySketch an energy diagram that shows a conformational analysis of 2,2-dimethylpropane. Does the shape of this energy diagram more closely resemble the shape of the energy diagram for ethane or for butane?
Organic Chemistry
General organic chemistryThe animation starts with a roughly spherical collection of surfactant molecules, called a micelle, at the top. Which groups point into the center of the micelle?
the nonpolar organic groups
the ionic head groups
Organic Chemistry
General organic chemistryWhich of the following objects are chiral?
Check all that apply.
a screw
a remote control device
a needle
a mug with BOB written to one side of the handle
a mug with MOM written to one side of the handle
a mug with MOM written opposite the handle
a chair
a mug with BOB written opposite the handle
Organic Chemistry
General organic chemistryA 535.0-mL aliquot of 0.860 M aqueous potassium hydroxide is mixed with 535.0 mL of 0.860 M aqueous magnesium nitrate.
a Write a balanced chemical equation for any reaction that occurs.
(Use the lowest possible coefficients. Be sure to specify states such as (aq) or (s). If a box is not
needed, leave it blank.)
Organic Chemistry
General organic chemistryThe compound chromium(III) nitrate is a strong electrolyte. Write the reaction when solid chromium(III) nitrate is put into water. I
Organic Chemistry
General organic chemistryThe compound iron (III) acetate is a strong electrolyte. Write the reaction when solid iron(III) acetate is put into water.
Organic Chemistry
General organic chemistryThe compound sodium iodide is a strong electrolyte. Write the reaction when solid sodium iodide is put into water. Include states of matter in your answer.
Organic Chemistry
General organic chemistryBeCl₂ in vapour state above 1200 K exists as A and below 1200 K exists as B. Which of the following is incorrect about structures A and B.
In structure A, the hybridization of Be is sp
In structure B, the hybridization of Be is sp²
In structure B, the hybridization of Be is sp³
The structure of A is linear
Organic Chemistry
General organic chemistryWhen natural gas (methane) burns, it reacts with oxygen in the air to form two new compounds, carbon dioxide and water. If 100 grams of methane and 100 grams of air are combined in a sealed container, and the mixture is allowed to react, what mass will be present in the container after the reaction takes place? The mass that will be present in the container is
Organic Chemistry
General organic chemistryAdd the unshared (lone) electron pairs to the structure in the drawing window below.
• Include all valence lone pairs in your answer.
• Should you want to restart the exercise, the drop-down menu labeled == starting points == car used to redraw the starting molecule on the sketcher.
Organic Chemistry
General organic chemistryThe compound nickel (II) sulfate is a strong electrolyte. Write the reaction when solid nickel (II) sulfate is put into water.
Organic Chemistry
General organic chemistryIn the laboratory you dissolve 14.0 g of cobalt(II) bromide in a volumetric flask and add water to a total volume of 500 mL.
What is the molarity of the solution?
What is the concentration of the cobalt(II) cation?
What is the concentration of the bromide anion?
Organic Chemistry
General organic chemistryWhich is the correct condensed formula for difluoropropane?
CH₂CHF2
CH₂CH₂CHF2
CH3CH₂F2
CH₂F2
CH3CH₂F
Organic Chemistry
General organic chemistryMatch the function with the most likely compound:
Refrigerant
Scents and flavorings
Steroidal hormone
Antiseptic for surgery
Component of butter and cell
membranes
Fuel
Organic Chemistry
General organic chemistryWhat is the ionization energy of the element whose electron configuration is [Ne]3s23p¹? Include the correct units and then Describe the general trend in ionization energy as the atomic number increases down a group and The lowest ionization energies tend to belong to which group?
Organic Chemistry
General organic chemistryWhat is the name for this molecule: CH3CH₂CH₂CH₂CH₂CH₂NH₂
propylamine
heptyl amine
pentylamine
hexyl amine
Organic Chemistry
General organic chemistryThe elementary reaction
2 H₂O(g) 2 H₂(g) + O₂(g)
proceeds at a certain temperature until the partial pressures of H₂O, H₂, and O₂ reach 0.075 bar, 0.0040 bar, and 0.0045 bar,
respectively. What is the value of the equilibrium constant at this temperature?
K =