Editing Answers To 2023-2024 Chem328 Review HW For Sig Figs And Fundamental Principles Of Chemistry
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Answers to [[2023-2024 Chem328 Review HW for Sig Figs and Fundamental Principles of Chemistry]] homework handout.<br> <br> 1) Matter ( I call them particles) and Energy<br> <br> 2) All substances are composed of particles that are in constant motion and sometimes collide/interact.<br> <br> 3a) Conservation of Mass - In a physical process and/or chemical reaction, mass is neither created nor destroyed (i.e. has to be conserved/accounted for).<br> 3b) Conservation of Energy - In a physical process and/or chemical reaction, energy is neither created nor destroyed (i.e. has to be conserved/accounted for). Also called First Law of Thermodynamics<br> <br> 4) Coulomb's Law ( I called it Coulombic Force, CF).<br> <br> 5) When particles collide, they can either<br> a) stay same - called physical change or<br> b) reorganize/rearrange - called chemical change (also called chemical reaction).<br> <br> 6) <br> <br> <br> <br> <br> <br> 7) Less energy but higher CF to nucleus (conversely an electron in a higher energy level, further away from nucleus, has more energy but has a lower CF to nucleus) <br> <br> 8) Release/give off valence electron (ve<sup>-</sup>) (because these ve<sup>-</sup> tend to be in higher energy level so less CF to nucleus).<br> <br> 9) Keep or gain ve<sup>-</sup> (because these ve<sup>-</sup> tend to be in lower energy levels so more CF to nucleus).<br> <br> <br> <br> <br> 10) Intramolecular forces are forces that hold the "particle together" whereas Intermolecular forces are between particles (for molecules only now). There are three Intramolecular forces:<br> a) Metallic bond is when two or more metal elements get close to each other. (all elements release ve<sup>-</sup><br> b) "Ionic bond" is when a metal and non-metal elements get close to each other.(transfer ve<sup>-</sup>)<br> c) Covalent bond is when two non-metal elements (can have more than 2) get close to each other. (share ve<sup>-</sup>)<br> <br> Answers to Question 11, 12, and 13 on separate sheet<br> <br> 14)Distribution of electrons. Unevenly distributed electrons cause polar molecules whereas "overall/on average" distributed electrons cause non-polar molecules.<br> <br> 15) Activation energy (E<sub>ac</sub>) is the minimum amount of energy for a set of reactants to form a set of products.<br> <br> 16) Besides Activation energy (E<sub>ac</sub>), the particles must be in the spacial orientation (close enough to collide and in correct 3-D location compared to other reacting particles). Of course, Effective collision (EC) of reactants cause products to be made.<br> <br> 17) Kinetics<br> <br> 18) In a reversible reaction, the products can have Effective collision causing products to rearrange back into reactant particles whereas an irreversible reaction products can NOT rearrange back into reactant particles.<br><br> 19) False ( <b>A BAD WORDED QUESTION</b> since the first (E<sub>ac</sub>) needs to be absorbed by an Exothermic reaction but no other since the further set of reactants can use the releasing energy for their (E<sub>ac</sub>) so no more outside energy is needed).<br> <br> 20) Value of item and measuring device explanation (i.e. what scale to use)<br> <br> 21) Precision<br> <br> 22) Kg<br> <br> 23) Your choice from notes<br> <br> 24) Kelvin<br> <br> 25) mol (not mole that is the name)<br> <br> 26) Ion (since ion is a charge element that either released or gained a ve<sup>-</sup>, there must be cation and anion. That is what the "formula unit" explains include elements/ions and how many of each) <br> <br> 27) 4<br> <br> 28) 3.0E2g or 3.0X10<sup>2</sup>g<br> 29) 3E2g or 3X10<sup>2</sup>g<br> 30) 3.00E2g or 3.00X10<sup>2</sup>g<br> <br>
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