Me with these problems! i'm stumped!

In a closed or isolated system , matter can not be created or destroyed. it can change forms but is conserved true or false

Write a brief passage describing a neutral atom of nitrogen-14 (n-14). describe the number of protons, neutrons, and electrons in the atom, where each type of particle is located, and how the terms atomic number, mass number, and atomic mass are related to the particles. use the periodic table to you. 14 protons and eletrons since its a neutral atom

Answer asap need by wednesday morning calculate the ph of 0.16m ch3cooh which has ka = 1.74 x 10-5 mol dm-3 best answer will be brainliest