Avogadro’s law. Gas mixtures
Answers are for parents and teachers.
1
What volume do 14 g of nitrogen (M = 28 g/mol) occupy under normal conditions?
11.2 L
2
An evacuated 2.24 L flask (n.c.) becomes 3.2 g heavier when filled with an unknown gas. Find the molar mass of the gas and say which gas it could be.
M = 3.2·22.4/2.24 = 32 g/mol — for example oxygen O₂.
3
Find the density of butane C₄H₁₀ (M = 58 g/mol) relative to air.
2
4
What is the volume fraction in percent of O₂ in a mixture of 20 L O₂ and 5 L N₂?
80
5
Why do 1 L of H₂ and 1 L of O₂ (under the same conditions) have different masses?
The number of molecules is equal, but the molar masses differ (2 and 32 g/mol).