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Sun 24 Nov, 2013 10:35 am
How does the density of helium compare to the density of oxygen and nitrogen?
You can compare yourself:
Quote:Name: Helium
Symbol: He
Atomic Number: 2
Atomic Mass: 4.002602 amu
Melting Point: -272.0 °C (1.15 K, -457.6 °F)
Boiling Point: -268.6 °C (4.549994 K, -451.48 °F)
Number of Protons/Electrons: 2
Number of Neutrons: 2
Classification: Noble Gas
Crystal Structure: Hexagonal
Density @ 293 K: 0.1785 g/cm3
Color: colorless
Quote:Name: Oxygen
Symbol: O
Atomic Number: 8
Atomic Mass: 15.9994 amu
Melting Point: -218.4 °C (54.750008 K, -361.12 °F)
Boiling Point: -183.0 °C (90.15 K, -297.4 °F)
Number of Protons/Electrons: 8
Number of Neutrons: 8
Classification: Non-metal
Crystal Structure: Cubic
Density @ 293 K: 1.429 g/cm3
Color: colorless
Quote:Name: Nitrogen
Symbol: N
Atomic Number: 7
Atomic Mass: 14.00674 amu
Melting Point: -209.9 °C (63.250008 K, -345.81998 °F)
Boiling Point: -195.8 °C (77.35 K, -320.44 °F)
Number of Protons/Electrons: 7
Number of Neutrons: 7
Classification: Non-metal
Crystal Structure: Hexagonal
Density @ 293 K: 1.2506 g/cm3
Color: colorless
@melodic,
melodic wrote:How does the density of helium compare to the density of oxygen and nitrogen?
It's different. That's how it compares. Sheesh, in the amount of time it takes you to post the homework question you could have googled the answer.
@melodic,
At room temperature and pressure they all behave like ideal gasses--so their molar volume is the same--so the density is proportional to their molecular weight. Note oxygen, nitrogen and hydrogen are diatomic molecules where helium is mono-atomic.
Rap