Why does the density of gas in a hot air balloon decrease as the gas is heated?
1 Answer
Jun 24, 2017
The density
where

#M# is the molar mass of the gas (in#"g/mol"# ) 
#P# is the pressure of the gas (in#"atm"# ) 
#R# is the universal gas constant, equal to#0.082057("L"·"atm")/("mol"·"K")# 
#T# is the absolute temperature of the gas (in#"K"# )
We can see from this relationship that the density (