What is a substance and what are the two types of substances?

The two types of substances are elements and compounds.

Explanation:

A pure substance is one in which the composition is definitive and constant throughout, and that has distinct chemical properties. These substances are comprised of only one entity, not a mixture of two or more.

Elements are pure substances, assuming they are free of imperfections, because they are made of only one type of atom.

Compounds are also pure substances, like water, table salt, table sugar, etc. because they are comprised of one type of compound (H2O, NaCL, C6H1206,etc)

idk

explanation:

dasdad

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.