Solved

Passage Ethanol Is an Important Source of Energy That Is Frequently

Question 157

Multiple Choice

Passage
Ethanol is an important source of energy that is frequently used as a supplement to gasoline.  It can be obtained from renewable resources such as the cellulose found in plant matter.  When subjected to a process called gasification, the plant mass is converted to a mixture called syngas, composed predominantly of carbon monoxide and molecular hydrogen.  Syngas can be passed over a rhodium catalyst to generate ethanol and other products.  After using this method, a group of researchers analyzed the resulting products by gas chromatography using helium as a carrier gas.  The results are shown in Figure 1.
Passage Ethanol is an important source of energy that is frequently used as a supplement to gasoline.  It can be obtained from renewable resources such as the cellulose found in plant matter.  When subjected to a process called gasification, the plant mass is converted to a mixture called syngas, composed predominantly of carbon monoxide and molecular hydrogen.  Syngas can be passed over a rhodium catalyst to generate ethanol and other products.  After using this method, a group of researchers analyzed the resulting products by gas chromatography using helium as a carrier gas.  The results are shown in Figure 1. <strong>Figure 1</strong>  Gas chromatograph of syngas catalysis productsMass spectrometry revealed that the process yielded similar amounts of ethanol, acetic acid, and acetaldehyde, with trace amounts of ethane.  In addition, the ethanol peak was found to be contaminated with ethyl acetate.  Another group of researchers in the same laboratory had recently produced Compound 1 as a by-product in a separate reaction.  They combined Compound 1 with purified ethyl acetate to form megestrol acetate, a drug used in the treatment of certain cancers.  This reaction also produced ethanol, as shown in Scheme 1. <strong>Scheme 1</strong> Adapted from Lopez L, Velasco J, Montes V, Marinas A, Cabrera S, Boutonnet M, Järås S. Catalysts  2015. -In Scheme 1, conversion of Compound 1 to Compound 2 most likely begins with which of the following steps? A) Nucleophilic attack by water, causing iodide to leave B) Deprotonation of water to enhance its nucleophilicity C) Formation of a carbocation as iodide leaves D) Protonation of iodide to form a better leaving group Figure 1  Gas chromatograph of syngas catalysis productsMass spectrometry revealed that the process yielded similar amounts of ethanol, acetic acid, and acetaldehyde, with trace amounts of ethane.  In addition, the ethanol peak was found to be contaminated with ethyl acetate.  Another group of researchers in the same laboratory had recently produced Compound 1 as a by-product in a separate reaction.  They combined Compound 1 with purified ethyl acetate to form megestrol acetate, a drug used in the treatment of certain cancers.  This reaction also produced ethanol, as shown in Scheme 1.
Passage Ethanol is an important source of energy that is frequently used as a supplement to gasoline.  It can be obtained from renewable resources such as the cellulose found in plant matter.  When subjected to a process called gasification, the plant mass is converted to a mixture called syngas, composed predominantly of carbon monoxide and molecular hydrogen.  Syngas can be passed over a rhodium catalyst to generate ethanol and other products.  After using this method, a group of researchers analyzed the resulting products by gas chromatography using helium as a carrier gas.  The results are shown in Figure 1. <strong>Figure 1</strong>  Gas chromatograph of syngas catalysis productsMass spectrometry revealed that the process yielded similar amounts of ethanol, acetic acid, and acetaldehyde, with trace amounts of ethane.  In addition, the ethanol peak was found to be contaminated with ethyl acetate.  Another group of researchers in the same laboratory had recently produced Compound 1 as a by-product in a separate reaction.  They combined Compound 1 with purified ethyl acetate to form megestrol acetate, a drug used in the treatment of certain cancers.  This reaction also produced ethanol, as shown in Scheme 1. <strong>Scheme 1</strong> Adapted from Lopez L, Velasco J, Montes V, Marinas A, Cabrera S, Boutonnet M, Järås S. Catalysts  2015. -In Scheme 1, conversion of Compound 1 to Compound 2 most likely begins with which of the following steps? A) Nucleophilic attack by water, causing iodide to leave B) Deprotonation of water to enhance its nucleophilicity C) Formation of a carbocation as iodide leaves D) Protonation of iodide to form a better leaving group Scheme 1
Adapted from Lopez L, Velasco J, Montes V, Marinas A, Cabrera S, Boutonnet M, Järås S. Catalysts  2015.
-In Scheme 1, conversion of Compound 1 to Compound 2 most likely begins with which of the following steps?


A) Nucleophilic attack by water, causing iodide to leave
B) Deprotonation of water to enhance its nucleophilicity
C) Formation of a carbocation as iodide leaves
D) Protonation of iodide to form a better leaving group

Correct Answer:

verifed

Verified

Unlock this answer now
Get Access to more Verified Answers free of charge

Related Questions

Q152: A 100-mL aqueous HCl solution was made

Q153: Passage<br>A group of students studied the reactivity

Q154: The compound shown below has selected carbons

Q155: Passage<br>Chloramphenicol (Compound <strong>1</strong>) is an antibiotic that

Q156: Passage<br>Ethanol is an important source of energy

Q158: Four alkyl halides: bromomethane, 2-bromobutane, 2-bromo-2-methylpropane, and

Q159: Passage<br>Malaria is caused by the parasite Plasmodium

Q160: Passage<br>High blood pressure, or hypertension, is a

Q161: Which separation technique is optimal for purification

Q162: A carboxylic acid is reacted with NaOH