In 1953, Stanley Miller and Harold Urey performed an experiment at the University of Chicago to test the hypothesis that the conditions of the early Earth would have favored the formation of larger, more complex organic molecules from basic precursors. The experiment, as shown below, consisted of sealing basic organic chemicals (representing the atmosphere of the primitive Earth) in a flask, which was exposed to electric sparks (to simulate lightning) and water vapor. After one day of exposure, the mixture in the flask had turned pink in color, and later analysis showed that at least \(10 \%\) of the carbon had been transformed into simple and complex organic compounds including at least 11 different amino acids and some basic sugars. No nucleic acids were detected in the mixture. 6\. A scientist believes that the Miller-Urey experiment failed to yield the remaining amino acids and the nucleic acids because of the absence of critical chemical substrates that would have existed on the primordial Earth due to volcanism. Which of the following basic compounds, which are associated with volcanism, would NOT need to be added in a follow-up Miller-Urey experiment? (A) \(\mathrm{H}_{2} \mathrm{~S}\) (gas) (B) \(\mathrm{SiO}_{2}\) (silica) (C) \(\mathrm{SO}_{2}\) (D) \(\mathrm{H}_{3} \mathrm{PO}_{4}\) (phosphoric acid)

Step by step solution

01

Examine option (A)

Analyze the role of \(\mathrm{H}_2 \mathrm{S}\) (hydrogen sulfide) in chemistry. Hydrogen sulfide is a simple and reductive molecule that can contribute to the creation of organic molecules, including amino acids and nucleic acids. This compound would likely be a useful chemical substrate in a follow-up Miller-Urey experiment.

02

Examine option (B)

Now let's consider \(\mathrm{SiO}_{2}\) (silica) as a potential compound to use. Silica is chemically inactive and is often used as a structural support material rather than a substrate for chemical reactions. Therefore, it is unlikely that silica would be necessary in a follow-up Miller-Urey experiment as it is not involved directly in the formation of organic molecules from precursors. This could be the correct option, but let's examine options (C) and (D) as well.

03

Examine option (C)

Next, we need to look at the role of \(\mathrm{SO}_{2}\) (sulfur dioxide). Sulfur dioxide is a strong reducing agent and can be involved in chemical reactions that lead to the formation of organic molecules. Such a compound could be helpful in a follow-up Miller-Urey experiment, as it might stimulate the formation of more complex molecules.

04

Examine option (D)

Finally, we need to analyze \(\mathrm{H}_{3} \mathrm{PO}_{4}\) (phosphoric acid). Phosphoric acid is an essential component of nucleic acids and a necessary reactant for phosphorylation and dephosphorylation processes that regulate cellular metabolism. Including phosphoric acid in a follow-up Miller-Urey experiment might increase the chances of obtaining nucleic acids, adding further support for the volcanic hypothesis.

05

Choose the correct compound

After examining options (A), (B), (C), and (D), we can conclude that \(\mathrm{SiO}_{2}\) (silica) (option B) is the compound that would not need to be added in a follow-up Miller-Urey experiment. This is because silica is chemically inactive and does not contribute towards the formation of organic molecules from precursors. The other compounds have potential roles in promoting organic molecule formation and thus might need to be included in a follow-up experiment. Therefore, the correct answer is (B) \(\mathrm{SiO}_{2}\).

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