At #NTP#, for a DIATOMIC gas, how many atoms constitute a #5.6*L# volume?
2 Answers
Explanation:
We're asked to calculate the number of atoms in
To do this, we can use the idealgas equation:
where

#P# is the pressure exerted by the gas, in units of#"atm"# (at NTP, the pressure is defined as#1# #"atm"# 
#V# is the volume occupied by the gas, in units of#"L"# (given as#5.6# #"L"# ) 
#n# is the number of moles of gas present (we'll need to find this) 
#R# is the universal gas constant, equal to#0.082057("L"·"atm")/("mol"·"K")# 
#T# is the absolute temperature of the gas, in units of#"K"# (the temperature at NTP is defined as#20^"o""C"# , which is
#20^"o""C" + 273.15 = 293.15# #"K"# )
Plugging in known values, and solving for the quantity,
Using Avogadro's number, we can convert from moles of gas to molecules:
We're given that the gas is diatomic, meaning there are two atoms per molecule, so the total number of atoms is
Approx.
Explanation:
So far as I know
But we are not finished there. We were asked for the NUMBER of ATOMS of
Note that looking at last year's exam paper they quoted both