Answer:
The Miller-Urey experiment was conducted to simulate the conditions on Earth when life arose, and see if a chemical evolution could occur. This experiment was performed without oxygen, because they knew that if oxygen was added, the amino acids would oxidize. In particular, the experiment intended to simulate a volcanic eruption was analyzed.
Thus, particles of water, methane, ammonia and hydrogen were exposed to high temperatures and electric discharges that simulated these eruptions, during a determined period. Later, it was observed that organic compounds had emerged from this exposure, which allowed us to infer one of the hypotheses regarding the origin of life on Earth.
