What does a particular point on a line of a phase diagram represent? A. The pressure created by the kinetic energy of molecules at a
particular temperature
B. The maximum temperature a substance can exist at without
bonds breaking
C. The melting point or boiling point of a substance at a specific
pressure
D. The conditions in which temperature and pressure have equal
effects on a substance

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.

c. electrical charges of ionic bonds.