Answer:
According to the Big Bang theory, the first two elements to form in the universe were hydrogen and helium. The Big Bang theory is the prevailing cosmological model for the observable universe from the earliest known periods through its subsequent large-scale evolution. It suggests that the universe began as an extremely hot and dense point, and then rapidly expanded and cooled over billions of years, eventually forming the stars, galaxies, and other structures that we observe today.
During the first few minutes after the Big Bang, the temperature and density of the universe were so high that atomic nuclei could form through a process known as nucleosynthesis. This process initially produced mainly hydrogen and helium, with trace amounts of lithium and beryllium. The heavier elements were formed later, through processes such as stellar nucleosynthesis in the cores of stars and supernova explosions.
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