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Chemistry Period 4, Shwetha Anand - Coggle Diagram

- - - - orbital shapes are the shapes where 90% of the electrons would be located inside an atom, and these shapes depend on the energy of the element
        
        s shapes are spheres(n=1+), p shapes are petals(n=2+), d shapes are 5 dumbells(n=3+), f shapes are 7 orbitals (n=4+)
        
        2 columns on the periodic table account for 1 orbital level, and within each orbital there's a certain number of 2e's, each with a different spin
    - - s shapes are spheres(n=1+), p shapes are petals(n=2+), d shapes are 5 dumbells(n=3+), f shapes are 7 orbitals (n=4+)
    - - Noble gases can have a full valence shell w/ 8 electrons, making them stable, and ions look to replicate this by either gaining or losing electrons
      - when filling up cations, do it in the opposite order, removing from the top first
    - - absorption: when the atom is given energy(missing bands), emission: stealing energy(extra bands) and these can displayed sometimes through light but differ per element
      - Noble gases can have a full valence shell w/ 8 electrons, making them stable, and ions look to replicate this by either gaining or losing electrons
- - - - When balancing chemical reactions, you never change the subscripts of the substance, only the coefficients. Always work in pencil and do oxygen last
    - - There's 5 types of reactions; Synthesis are when 2 things combine into 1, Decomposition is when 1 thing splits into 2, Combustion is burning, single replacement is when a single element is swapped, and double replacement is when 2 elements swap
      - Certain elements need to remain diatomic, keep in mind
    - - 1 mole = 6.02 x 1023 objects, and it usually moves grams->moles->molecules
- - - - bonds form to lower potential energy between atoms’ charged particles, and there's 3 types of bonds all differing in usage and strength
        
        Ionic bonds are the transfer of electrons, with high electronegativity that occur between a metal and a nonmetal, Covalent bonds are the sharing of electrons, with high electronegativity and ionization energy, between two nonmetals, Metallic bonds are when the valence electrons delocalize and float between 2+ metals
      - Cations are positive, Anions are negative, Monoatomic elements have 1, whereas polyatomic elements have 2+ elements
      - When naming, the process differs for ionic vs. covalent, For Ionic, cations keep the element name, anions add on -ide, and polyatomic ions keep element name. For COvalent molecules/bonds, Use greek prefixes for 1-10(not mono), drop the two "o" vowels and the last element ends in ide
    - - you want the lowest possible combo
      - the crossing over method is when you identify the cation/anion, write down the charges and symbols, then exchange (be wary fo polyatomic)
    - - Most, not all, molecules follow the octet rule. When drawing a dot structure, the least electronegative material goes in the center and hydrogen's on the outside
      - Drawing anions = use brackets + add as many val e- as ion has (AKA draw all 8)
        Drawing cations = use brackets + subtracts as many val e- as ion has (AKA draw 0)
    - - polar molecules are when electrons are unevenly shared, and nonpolar molecules are when electrons are evenly shared
- - - - when there's a specific chemical that runs out sooner than the other, and the goal's to determine which one runs out first and how much is left-- we know it's limited if we're given two starting values.
        
        To calculate this, we've got five steps; make sure everything is in moles, make a have vs. need table, identify the limiting reagent, then do stoich with limiting and find excess
    - - how much of a molecule's mass is from one specific molecule? Part/whole*100,
      - Empirical formulas are the simplest form, while molecular formula isn't always the simplest form
        
        Empirical formula:
        
        Percent to mass
        
        Mass to moles
        
        Divide by small
        
        Multiply by whole (if necessary)
        
        Molecular formula
        
        Find empirical formula’s molar mass
        
        Divide molecular formula’s mass by empirical formula
        
        Multiply empirical formula subscripts by multiplier found in step 2
- - - - Stoichiometry = calculating amounts of reactants and/or products involved in reaction, and must always happen with a BALANCED reaction
      - Mole ratios are the key here
      - Theoretical yield is the amount that's expected to be made, and actual yield is how much we produced. To find the % yield, we do (actual yield)/(theoretical yield)*100
- - - - Aa+Bb=Cc+Dd
  - - - Write the skeleton rate law
      - Look at experimental data/chart
      - Find 2 trials:
      - The [ ] of 1 substance is held constant
      - The [ ] of 1 substance is being changed
      - Look to see how the rate changes when you vary the [ ] of only ONE substance
      - Find which exponent on the [ ] change would result in the observed rate change = ORDER
      - Repeat for each additional reactant
      - ** If you don’t have 2 trials but 1 reactant constant, solve for the orders you can. THEN, pick 2 trials and plug in known values
- - - - We always use Kelvin, atm's(depends on problem), and there's five basic gas laws
      - Boyle's law
        
        P1 V1 = P2 V2
        
        Temp/moles = constant
        
        Indirect/inverse relationship between pressure and volume
      - Charles' law
        
        V1 / T1 = V2 / T2
        
        Pressure/moles = constant
        
        Direct relationship between temp/volume
        
        Graph doesn’t go to zero b/c there will always be space between particles
      - Gay-Lussacs law
        
        P1 / T1 = P2 / T2
        
        Volume/moles = constant
        
        Direct relationship between temp/pressure
        
        Low temp = solid/liquid; dotted line represents this
      - Avogadro's law
        
        V1 / n1 = V2 / n2
        
        Pressure/temperature = constant
        
        Direct relationship between moles/volume
      - Combined Gas law
        
        P1 V1 / T1 = P2 V2 / T2
        
        Moles = constant
        
        Combines most common variables together (not common to change moles of gas)
    - - PV=nRT, where pressurevolume=molesn*temp
      - Ideal gas isn't always applicable to real gases, as it doesn't account for attraction/repulsion and others
- - - - solutions are made of solute+solvents combined, and these can form different levels of saturation
        
        solubility is affected by both pressure and temperature
      - dissolving is when the solute and solvent combine, but dissosciating is when the ionic compound breaks down
    - - there's multiple calculations that need to be made for solutions
        
        Mass percent of chem
        Ratio of masses expressed as %
        Mass % = [mass of solute]/[mass of solution] * 100
        
        parts per million: ppm = [mass of solute]/[mass of solution] * 1000000
        
        Grams per liter
        
        Ratio of mass of solute to volume of solution
        
        Easy with solid solute dissolved in liquid; used to test solubility
        
        Grams/Liter = [mass of solute]/[volume of solution]
        
        Mole fraction:
        Ratio of solute (mols→ nA) to mols of total solution→ nA + nB
        A = XA = nA/[nA + nB]
        
        Molarity:
        Ratio of mols solution to to liters of solution; like g/L but better conversions
        Molarity = M = [mols of solute]/[Liters of solution]
- - - - there's 3 classifications, arrhenius, bronsted-lowry, and lewis
        
        water can be both an acid or a base, Amphoteric = chemical that can be either an acid or base, depending on what it’s paired with, Conjugate Base = what acids turn into after losing proton/hydrogen
    - - Steps
        
        Hydro
        
        Root of other element
        
        -ic
        
        Acid
      - Oxyacids
        
        Starts with root of ion (not H or O; sometimes starts with per/hypo→ with # of oxygens present)
        
        -ic or -ous →
        
        Ends with -ate → -ic
        
        Ends with -ite → -ous
        
        Extra O than -ate → Per-
        
        Fewer O than -ite → Hypo-
- - - - Q=mCAT, where c is specific heat, m is moles, AT is change in temp and q is energy lost or gained
        
        these changes in heat can be either endo or exothermic
    - - Calorimetry is the measure of heat gained or lost in a reaction
        
        Using the first law of thermodynamics, we know that energy in=energy out, so we just do mCAT=-mCAT to find our answer
    - - Heating and cooling show up as a slope, while phase changes remain as a constant/flat line
        
        Q=mCAT can be used for heating and cooling but for phase change, it has to be slightly different, with latent heat insteead
    - - enthalpy is heat change in reaction, endothermic reaction graphs end up lower than products, the triple point on a graph is a point in pressure and temp. where all three forms can exist, melting is different from the other forms
- - - - equilibrium is the point within a reversible reaction where both the product and the reactant are at the same rate
        
        reaction stressors are temp+pressure/volume, and these only apply to aqueous things, not solids or liquids
      - Le chat states that if stress applied to rxn @ equil → rxn changes to relieve stress so it finds a new equil. point where the forwards rate = backwards rate = undo what was done
    - - Keq=products/reactants, and it's calculated with Law of Mass Action = to calculate Keq
      - if k>1, it favors the products but if K<1, it favors reactants
    - - ICR tables are used to find out the concentration of products and reactants in a reversible reaction
      - Steps
        
        Fill in given initial concentration for known [], others are 0
        
        Add or subtract (coefficient)x depending on reactant or product, respectively
        
        Combine and write in 3rd row
        
        Write as law of mass action
        
        Plug in known values
        
        Solve for x using quadratic formula
        
        Plug in x values in answer row to solve
- - - - Nonzero numbers always count, leading zeroes never count, captive zeroes always count and trailing zeroes only count if it's after a decimal
        
        When adding or subtracting, the answer's based on the least number of decimal places; when multiplying or dividing, the answer's based off of the least number of sig figs
  - - - Calculated with the formula of (mass of isotope1* %abundance)+mass of isotope 2 etc...