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Question

What is the mass of a large balloon used to sample the upper atmosphere that is filled with 355 m^3 of helium? What is the mass of the helium in kg?

Answer 1

mass (m) equals density (ρ) multiplied by volume (V)

m = ρV

You can either look up the density of helium in a book or google it. The density of helium is 0.1784 kg/m³ at STP (standard temperature and pressure). Assuming STP:

m = (0.1784)(355) = 63.3 kg