8.11 × 10²⁸ atoms of helium are contained in a 539 kg helium.
For every mole of a substance there are 6.022 × 10²³ representative particles of that substance. The amount of particles in one mole of substance is called Avogadro's number.
<u>Further Explanation</u>
To convert from the number of moles to number of representative particles, the formula below may be used:

For this problem, the number of helium atoms can be determined by plugging in the given values in the equation above. But before plugging in, the mass of helium must first be converted to grams. Then, the mass is converted to the number of moles and the number of moles is converted to the number of particles using Avogadro's number.

Since the given has only three significant figures, the final answer must also have three significant figures. Therefore, the answer rounded to correct significant figures is:

<u>Learn More</u>
- Learn more about representative particles brainly.com/question/896931
- Learn more about Avogadro's number brainly.com/question/229300
- Learn more about mole conversions brainly.com/question/1370888
<u>Keywords: </u>moles conversion, Avogadro's number