2. an element's atomic number is the a. number of protons in an atom's nucleus. b. mass of the atom. c. weight of the atom. d. sum of the protons and neutrons in an atom.

A. number of protons in an atom's nucleus.

Explanation:

The number of protons in the nucleus in an atom is the atomic number of the element and it is characteristic of a chemical element and determines its place in the periodic table.

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.

hurricanes form when warm, moist air from the ocean surface quickly rises into the atmosphere and forms storm clouds and rain. when the clouds are formed, heat is released which warms the cool air in the upper regions of the atmosphere so that the cycle can continue. which two phases of the water cycle are repeated in this process?