Honors Chemistry Fall 2024 Review KEY PDF

1. **Zeroth law ("thermal equilibrium"):** Two systems in equilibrium with a third system are in thermal equilibrium with each other; example: if you leave a glass of cold water in a room, the water will absorb heat from the room until it is at the same temperature as the rest of th...

1. **Zeroth law ("thermal equilibrium"):** Two systems in equilibrium with a third system are in thermal equilibrium with each other; example: if you leave a glass of cold water in a room, the water will absorb heat from the room until it is at the same temperature as the rest of the room **First Law ("law of conservation"):** Energy can change forms, but is neither created nor destroyed; When you rub your hands together, the amount that your hands heat up equals the mechanical work done to rub your hands together **Second Law: Entropy** of an isolated system always increases; You would never see a scattered pile of cards leap off the table to form an ordered house of cards, but a house of cards will easily fall and scatter (a system can become more ordered, but it requires work from outside the system) **Third Law:** Entropy of a system approaches a constant value as its temperature approaches absolute zero; example: the entropy of a perfect crystal is zero 2. a. Temperature and pressure have a direct relationship - the pressure inside of the ball will increase b. **Zeroth Law** - the air inside of the ball will reach thermal equilibrium with its surroundings **First law** - the energy from the sun is absorbed by the ball, causing the air molecules to increase in kinetic energy; the energy from the sun is converted into kinetic energy by the air molecules **Second law -** the energy from the sun causes the air molecules inside of the ball to increase in kinetic energy, therefore increasing the entropy of the system 3. Pressure and volume have an indirect relationship - the pressure inside of the ball will increase. **Unit 2: Atomic Structure** **Learning Targets** ---------------------- ---------------------------------------------------------------------------------------------------------------------------------------------------------- **2.1** I can illustrate the structure of an atom and identify the location of protons, neutrons, and electrons **2.2** I can explain the functions of the subatomic particles **2.3** I can create/illustrate the development of the modern atomic theory over time using the discoveries of Dalton, Thomson, Rutherford, Bohr, and Heisenberg 4. **Subatomic Particle** **Proton** **Neutron** **Electron** ------------------------ ---------------------------------------- ------------------------------------------------------------ --------------------------------------------------- **Charge** **(+) positive** **Neutral** **(-) negative** **Location** **In the nucleus** **In the nucleus** **In the electron cloud surrounding the nucleus** **Function** **Determines the identity of an atom** **Provides stability in the nucleus with all the protons** **Determines the chemical properties of an atom** - - - - - - - - - - - - 5. In the Bohr model of the atom, electrons move in well-defined circular orbits around the nucleus. Each orbit represents a different energy level that electrons can occupy. In the Quantum Mechanical model of the atom, electrons occupy loosely-defined regions called orbitals. The shape of the orbitals differ depending on the energy level and sublevel they are found in. 6. Dalton stated that atoms are indivisible, meaning that they cannot be broken down into smaller pieces or portions. This was later disproved by the discovery of the subatomic particles (protons, neutrons, and electrons). **Learning Targets** ---------------------- -------------------------------------------------------------------------------------------------------------------------- **2.4** I can explain and calculate how wavelength, frequency, and energy relate to one another and the electromagnetic spectrum **2.5** I can relate element emission data to the electromagnetic spectrum 7. **E=h\*v E = (6.63x10^-34^)\*(4.68x10^18^) E = 3.10 x 10^-15^ J** 8. **C = ƛ\*v (v) = 3.00x10^8^ / (4.52x10^-7^) v = 6.64 x 10^14^ Hz** 9. **E = hv E = (6.626x10^-34^)\*(5.71x10^14^) E = 3.78 x 10^-19^ J** 10. **An electron in its ground state can absorb a quantum of energy and move to an excited state in a higher energy level around the nucleus. It will then release that energy as a photon of light and move back to its ground state.** **Unit 3: Nuclear Chemistry** **Learning Targets** ---------------------- ------------------------------------------------------------------------ **3.1** I can write nuclear equations for alpha, beta, and gamma radiation **3.2** I can distinguish between fission chain reactions and fusion reactions **3.3** I can give examples of applications of nuclear chemistry **3.4** I can do calculations with the half-life of a radioisotope. 🔢 11. - **^53^~26~ Fe → ^0^~-1~e + ^53^~27~** **Co** - **^38^~19~ K → ^4^~2~ He + ^34^~17~ Cl** 12. **There will be 4 half-life cycles (20/5 = 4)** **Time** **0** **5 days** **10 days** **15 days** **20 days** ------------ ---------- ------------ ------------- ------------- ------------- **Amount** **80 g** **40 g** **20 g** **10 g** **5 g** **There will be 5 grams left after 20 days.** 13. **There will be 2 half-life cycles (12 hours / 6 hours = 2 HL)** **Time** **0** **6 hours** **12 hours** ------------ ----------- ------------- -------------- **Amount** **30 mg** **15 mg** **7.5 mg** **There will be 7.5 mg left after 12 hours.** 14. Fusion = two smaller nuclei combining into a single larger nucleus Fission = a single large nucleus splitting into smaller nuclei; used in nuclear power plants  **Fusion Fission** **Unit 4: Periodic Table** **Learning Targets** ---------------------- ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------- **4.1** I can explain the chemical and physical properties in the historical development of the periodic table **4.2** I can determine the number of protons, neutrons, and electrons in an atom using various chemical notations **4.3** I can calculate the atomic mass of an element using its isotopic information **4.4** I can identify and predict the properties of chemical families (alkali metals, alkaline earth metals, halogens, noble gasses, and transition metals) on the periodic table **4.5** I can identify periodic trends based on elemental data (atomic radius, electronegativity, ionization energy) **4.6** I can determine the electron configuration of an element +-----------+-----------+-----------+-----------+-----------+-----------+ | | **Alkali | **Alkali | **Transit | **Halogen | **Noble | | | Metals** | Earth | ion | s** | Gases** | | | | Metals** | Metals** | | | +===========+===========+===========+===========+===========+===========+ | **Locatio | Group 1 | Group 2 | Groups | Group 17 | Group 18 | | n | or 1A | or 2A | 3-12 | or 7A | or 8A | | on the | | | | | | | periodic | | | | | | | table | | | | | | | (Group \# | | | | | | | )** | | | | | | +-----------+-----------+-----------+-----------+-----------+-----------+ | **Propert | Most | Reactive | Propertie | Most | Inert | | ies** | Reactive | Metals | s | Reactive | (unreacti | | | Metals | | of Metals | Nonmetals | ve) | | | | Loses | | (some are | | | | Loses | Electrons | Can form | gases) | Gases | | | Electrons | | 2 | | | | | | Forms + | different | Forms - | 8 valence | | | Forms + | IONS | ions | IONS | electrons | | | IONS | | | | | | | | Cations | Ductile, | Anions | | | | Cation | | malleable | | | | | | 2 Valence | , | 7 valence | | | | 1 Valence | Electrons | good | electrons | | | | Electron | | conductor | | | | | | | s | | | | | | | of heat | | | | | | | and | | | | | | | electrici | | | | | | | ty | | | | | | | | | | | | | | Strong, | | | | | | | hard and | | | | | | | less | | | | | | | reactive | | | | | | | | | | | | | | Valence | | | | | | | Electrons | | | | | | | = s + d | | | +-----------+-----------+-----------+-----------+-----------+-----------+ | **Valence | 1 | 2 | Most have | 7 | 8 | | Electrons | | | 2 (s | | | | ** | | | shell) | | | | | | | since | | | | | | | they are | | | | | | | in D | | | | | | | block | | | +-----------+-----------+-----------+-----------+-----------+-----------+ | **Ionic | +1 | +2 | Varies - | -1 | n/a | | Charge** | | | depends | | | | | | | on loss | | | | | | | of e- = | | | | | | | they form | | | | | | | positive | | | | | | | ions | | | +-----------+-----------+-----------+-----------+-----------+-----------+ 15. Dmitri Mendeleev 16. Families or groups 17. Periods 18. Helium, Argon, Krypton, Xenon - the noble gases 19. - - - 20. 22 neutrons (Mass number - Atomic Number = Neutrons) 21. **Isotope Name:** **Abundance** **Mass** **Abundance\*Mass** ------------------- --------------------- ------------ --------------------------- Chlorine-35 75.53%/100 = 0.7553 34.969 amu 0.7553 \* 34.969 = 26.412 Chlorine - 37 24.47%/100 = 0.2447 36.966 amu 0.2447 \* 36.966 = 9.046 **Average: 35.458 amu** Average atomic mass = 35.458 amu **Unit 5: Chemical Bonding** **Learning Targets** ---------------------- ----------------------------------------------------------------------------------------------------- **5.2** I can express the number of valence electrons using electron dot diagrams **5.3** I can represent how different types of covalent bonds are formed by drawing electron dot structures **5.4** I can use the VSEPR theory to predict the shape of a molecule. 22. Molecular shape = trigonal pyramidal Bond angles = 109.5 23. Molecular shape = tetrahedral Bond angles = 109.5 **Learning Targets** ---------------------- ------------------------------------------------------------------------------------------------------------------------------------------ **5.1** I can determine the bond character based on electronegativity differences **5.6** I can explain how intramolecular & intermolecular attractions determine physical properties of molecular, ionic, and metallic substances 24. 25. The ions of an ionic compound are bonded together in an ordered, repeating arrangement of alternating positive and negative charges that form a crystalline structure. 26. Molecule - a group of two or more atoms covalently bonded together. As a solid, molecules are very close together and are not free to move. The molecules of a liquid are slightly farther apart and able to flow around each other. The molecules of a gas are extremely far apart and move independently. 27. - - - 28. - - - Use the electronegativity chart below as a reference for the following questions. electronegativitychart.png 29. a. The molecular geometry of the molecule is trigonal pyramidal. The electronegativity difference between Nitrogen and Hydrogen is.84 making all the bonds polar (greater than.5 difference). The molecule is polar due to having one lone pair of electrons and polar bonds being on the same side. (asymmetrical) b. The molecular geometry of the molecule is trigonal planar. The electronegativity difference between Boron and Chlorine is 1.12 making all the bonds polar (greater than.5 difference). The molecule is nonpolar due to having polar bonds being on opposite sides. (symmetrical) 30. Hydrogen bonding, dipole-dipole, london dispersion Use the electronegativity chart below as a reference for the following questions.  31. LC 2.12 Pic 2.JPG **Compound 1 Compound 2** Compound 2 would have the highest boiling point because it experiences dipole-dipole forces (stronger) and compound 1 only experiences London dispersion forces (weaker). Stronger forces require more energy, like higher boiling points, to separate molecules. 32. The metal cations are arranged in a crystal lattice structure similar to ionic compounds, while their valence electrons are freely moving throughout the lattice in what is called the "sea" of electrons. 33. a mixture of two or more elements with metallic properties 34. Alloys are created as they are stronger than each of the metals in their pure form. The presence of multiple atom types makes it more difficult for the layers to slide and rearrange, making the alloy strong. Alloys also have different purposes based on which metals are combined