The conversion of hydrogen into helium began about 2 minutes after the beginning of the expansion of the universe.Why was there no helium in the universe during the first 2 minutes?
A)There was no matter in the universe during the first 2 minutes
B)Collisions were too violent for helium to be stable during that time
C)No collisions occurred during the first two minutes
D)Neutrino disruption dominated during the first two minutes

Question

Quizplus · Accepted Answer

During the first two minutes after the Big Bang, the temperature and density of the universe were so high that collisions between particles were extremely violent. This prevented the formation of stable helium nuclei. It was only after the universe cooled down enough that the conversion of hydrogen into helium began.

The Conversion of Hydrogen into Helium Began About 2 Minutes