Passage IV
Introduction
Nitrobenzene (C6H5NO2) is a molecule consisting of a nitro group (-NO2) attached to a benzene ring (a ring of 6 carbon atoms connected by alternating single and double covalent bonds). A teacher asked 4 students to predict what carbon-containing products are formed when nitrobenzene and bromine (Br2) react in the presence of solid ferric bromide (FeBr3), and also how fast those products are formed. Figure 1 shows a representation of this reaction; each C atom is labeled with a number.
Student 1
The -NO2 partially donates electrons to the benzene ring, resulting in a relatively fast reaction between nitrobenzene and Br2. A new C-Br covalent bond is formed when electrons from a carbon atom of the benzene ring are transferred to one of the Br atoms of Br2. The reaction produces only 1 carbon-containing product: the H atom bound to C-2 is replaced by a Br atom.
Student 2
The-NO2 partially pulls electrons from the benzene ring, resulting in a relatively slow reaction between nitrobenzene and Br2. A new C-Br covalent bond is formed when electrons from a Br atom of Br2 are transferred to one of the carbon atoms of nitrobenzene. The reaction produces only 1 carbon-containing product: the H atom bound to C-3 is replaced by a Br atom.
Student 3
The-NO2 partially pulls electrons from the benzene ring, resulting in a relatively fast reaction between nitrobenzene and Br2. A new C-Br covalent bond is formed when electrons from a carbon atom of the benzene ring are transferred to one of the Br atoms of Br2. The reaction produces only 1 carbon-containing product: the H atom bound to C-4 is replaced by a Br atom.
Student 4
The-NO2 partially donates electrons to the benzene ring, resulting in a relatively slow reaction between nitrobenzene and Br2 . A new C-Br covalent bond is formed when electrons from a Br atom of Br2 are transferred to one of the carbon atoms in nitrobenzene. The reaction produces 2 carbon-containing products, and each product has only 1 Br atom. In one product, the H atom bound to C-2 is replaced by a Br atom, and in the other product, the H atom bound to C-4 is replaced by a Br atom.
25. Based on Student 2's prediction, which of the following figures shows a product of the reaction represented in Figure 1 ?
Your Answer is
Correct Answer is B
Explanation
According to the last sentence of Student 2, the only change is that Br replaced the H corresponding to C-3, so B fits the meaning of the question