in solid matter, atoms or molecules pack close to each other in fixed locations; in gases, atoms or molecules pack about as closely as they do in solid matter, but they are free to move;
Answer:

Explanation:
Hello,
In this case, since we can consider hydrogen gas as an ideal gas, we check the volume-pressure-temperature-mole relationship by using the ideal gas equation:

Whereas we are asked to compute the moles given the temperature in Kelvins, thr pressure in atm and volume in L as shown below:

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the mass of the shells will remain the same because you can not change mass even if you were to leave this planet and go to the moon your weight would change but your mass remains the same
Because their atoms have the same number of electrons in the highest occupied energy level
539.421ml would be the correct conversion