Question 5. 5. a chemist studies two forms of refined gasoline. which of the following branches of chemistry might the chemist use?
inorganic chemistry
physical chemistry
analytical chemistry
organic chemistry

Answer : Option D) Organic chemistry.

Explanation : As the chemist is studying two forms of gasoline, where both are organic chemicals hence they belong to organic chemistry as the branch. Also, the two forms of the refined gasoline can be used to study other features of gasoline in organic chemistry and the experiment can be help to analyze the gasoline in many ways.

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.