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To determine the fraction of the hydrogen atom's mass that is in the nucleus, we have to keep in mind that
a Hydrogen atom has 1 proton and 1 electron.
Protons are in the nucleus while electrons are in electron shells surrounding the nucleus.
The mass of the nucleus will be equal to the mass of 1 proton and we can express the fraction as follows:

So, the fraction of the hydrogen atom's mass that is in the nucleus is
0,9995. That means that almost all the mass of this atom is at the nucleus.
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C3H8 + O2 (please give me brainliest$
Answer:
I think C. Hope this Helps!
Explanation:
You slap some dough on to a beach and wait for it to become bread
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