CHEM 117 1st EditionExam # 1 Study Guide Lectures: 6-8Chapter 6Thermochemistry1. First Law of Thermodynamics: The total energy of the universe is constant. (Since energy is neither created nor destroyed, and since the universe does not exchange energy with anything else, its energy does not change)2. Kinetic energy vs. potential energy: -kinetic energy: associated with motion of an object (ex. A rolling billiard ball),-potential energy: associated with the position or composition of an object. (ex. Raising a ball off the ground)3. State function- the change in altitude depends only on the difference between the final and initial values, NOT on the path taken. 4. Heat and Work: - q (heat), + system gain thermal energy, - system loses thermal energy.-w (work), + work done on the system, - work done by the system- ΔE (change in internal energy), + energy flows into the system, - energy flows out of the system.5. Internal Energy Change Equation: ΔE= q + W 6. Endothermic- absorbs heat from surroundings (positive ΔH); Exothermic- gives off heat to its surroundings (negative ΔH).Heat Capacities:7. Q= m x Cs x ΔT 8. Enthalpy is the sum of its internal energy and the product of its pressure and volume: H = E + PV9. Change in Enthalpy: ΔH = ΔE + PΔV10. Enthalpy changes in a calorimetry experiment: qsoln = msoln X Cs, soln X ΔT-Bomb calorimetry occurs at constant volume and measures ΔE for a reaction.-Coffee-cup calorimetry occurs at constant pressure and measures ΔH for a reaction.Chapter 71. 1. Amplitude: vertical height of a crest-wavelength ( )λ : distance between adjacent crests-frequency (ν): the number of cycles that pass through a stationary point in a given period of time.2. Photoelectric effect: the observation that many metals emit electrons when light shines upon them. (when energetic light shines on a metal surface, the surface emits electrons, and the emitted electrons can be measured as an electrical current).3. Photon: E= hν/λ 4. h= 6.626 E -34 JxS5. -The energy of a photon is directly proportional to its frequency and inversely proportional to its wavelength.6. Diffraction: when a wave encounters an obstacle or a slit that is comparable in size to its wavelength, it bends around it. Interference: when a beam of light passes through two small slits,the two resulting waves interfere with each other. 7. Continuous Spectrum: there are no sudden interruptions in the intensity of the light as a functionof wavelength- the spectrum consists of light of all wavelengths. -Line spectrum: a particular element is always the same- it consists of the same bright lines at thesame characteristic wavelengths and can be used to identify the element. 8. De Broglie Wavelength: = h/mv **In this case, v is velocity. λ**According to the Bohr model, each spectra line is produced when an electron falls from one stable orbit, or stationary state, to another of lower energy. 9. Quantum numbers:- Principal quantum number: n- Angular momentum quantum number: l- Magnetic quantum number: ml- Spin quantum number: ms (all electrons have the same amount of spins, +1/2 and -1/2)10. The Rydberg equation: ΔE= -2.18E-18 J (1/nf^2) – [-2.18E-18J (1/ni^2)] 11. Orbitals-“p orbitals” (l=1): each principal level with n=2 or greater contains three p orbitals. They are not spherically symmetric like the s orbitals.-“d orbitals” (l=2): each principal level with n=3 or greater contains five d orbitals.-“f orbitals” (l=3): each principal level with n=4 or greater contains seven f orbitals. They have more lobes and nodes than d orbitals. 12. The lowest energy state is GROUND STATE.13. Each energy state with n>1 is excited state.Chapter 81. 1. Periodic property: a predictable property based on an element’s position on the periodic table.2. Aufbau principle: electrons are added to the lowest energy orbitals first adding to the next higher energy orbitals. 3. Pauli exclusion principle: no two electrons in an atom can have the same four quantum numbers (each electron has to have a unique set of quantum numbers)4. Electron configuration RULES:-Electrons will reside in the available orbitals of the lowest possible energy.-Each orbital can accommodate a maximum of two electrons.-Electrons will not pair in degenerate orbitals if an empty orbital is available. -Orbitals will fill in the order indicated in the figure. 5. Valence electrons- For the main group elements, the valence electrons are in the outermost principle energy level. 6. The group number of a main-group element is equal to the number of valence electrons for thatelement.7. The row number of a main- group element is equal to the highest principle quantum number of that element. 8. Properties of the Periodic Table:-As you move down a column, atomic radius increases.-As you move to the right across a period, atomic radius decreases. (Example from clicker questions: Na>Mg>N>O>F)-As you move down a column, ionization energy decreases because electrons in the outermost principal level are increasingly farther away from the positively charged nucleus and are therefore held less tightly.-As you move to the right across a row, ionization energy increases because electrons in the outermost principal energy level generally experience a greater effective nuclear