Explain at particle level whether seawater is a pure substance or a mixture

Seawater is a mixture of many different substances. Some of these substances can be observed when the water in seawater evaporates and leaves behind salt. Water, H2O, is a pure substance, a compound made of hydrogen and oxygen.

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.

i think the answer is terrae but not 100 percent sure. ▓▬▬ §