What was the mass of the original amount of hydrogen in the sun?

Answer 1

The original mass of hydrogen inside the Sun was about
0.73 x 1.99 x 10^33 gm = 1.5 x 10^33 gm. Here's how that quantity is found:

We believe that something like 73 % of the Sun's original content was hydrogen, the rest being helium and heavier elements.

Although the Sun has beeen converting matter into energy for about 4.65 x 10^9 years, that corresponds to less than 1 % of its matter having been so converted in that time, so it's a relatively negigible amount.

So, the original mass of hydrogen inside the Sun was about
0.73 x 1.99 x 10^33 gm = 1.5 x 10^33 gm.

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