1. a plant extract can be obtained with organic solvents such as acetone or ethyl alcohol, and is composed of plant pigments such as chlorophyll a and b, carotene, and xanthophylls. write a brief explanation about why a plant extract is a mixture, whether it is homogeneous or heterogeneous, and how it can be separated.
2. a scientist has a sample of a substance that could be magnesium, sodium, stainless steel, or copper. name two properties the scientist could use to identify the substance, and explain why the scientist could use each property to identify the 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.