Midterm 2 explain your answers! Each problem is worth 2 points. 1) To become a negative ion, does an atom lose or gain an electron? 2) What Is the cause of Brownian motion of dust and other small particles? 3) Some atom contains 29 electrons, 34 neutrons and 29 protons. What is its atomic number? 4) Why is the buoyant force on a submerged submarine appreciable greater than the force on it while it is floating? 5) If a submarine starts to sink, will it continue to sink to the bottom if no changes are made? 6) On what depends the pressure at the bottom of a pond? 7) In which form of heat transfer is a medium not required? 8) Which law of thermodynamics tells us whether heat flows from cold to hot or in the reverse direction? 9) If 100 J of heat is added to a system that does 40 J of external work, by how much is the internal energy of that system changed? increased or decreased? of water from 0 C to