What is meant by the Terrestrial and Hydrologic parts of Earth?

Not sure what you exactly mean, but I think what you are talking about are the spheres of earth (Lithosphere, Hydrosphere, Atmosphere, and Biosphere.)

Lithosphere (Terrestrial) is the land on earth. Hydrosphere (Hydrologic) is the water on earth.

I'm not sure if this is 100% correct but I'm guessing this is what you are referring to. It could be different across different science classes.

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.

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.