PLEASE HELP How many moles of helium gas are in 30.0L sample of He, if density of helium gas is 0.016 g/ml?

Moles of helium gas = 120

Explanation:

Given:

Volume of He = 30 L = 30,000 ml

Density of He = 0.016 g/ml

Find:

Moles of helium gas

Computation:

Mass = Volume of He x Density of He

Mass = 30,000 x 0.016

Mass = 480 gram

Moles of helium gas = 480 / 4

Moles of helium gas = 120

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

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