Search found 49 matches

by IanWheeler3F
Sun Dec 06, 2020 7:24 pm
Forum: Air Pollution & Acid Rain
Topic: acid rain
Replies: 10
Views: 186

Re: acid rain

If you think about statues made by the ancient Greeks and how long ago they were made you would think that they would be long gone because of the rain eroding them constantly. But they lasted so long because only very recently did CO2 levels spike and increase acidity and cause their destruction. Ac...
by IanWheeler3F
Sun Dec 06, 2020 7:14 pm
Forum: Lewis Acids & Bases
Topic: textbook 6.5
Replies: 2
Views: 19

Re: textbook 6.5

yeah, since SO3 is attached to three oxygens and then gains an attachment to one of the oxygens in H2O2, so SO3 accepts electrons making it a lewis acid, and then H2O2 the lewis base.
by IanWheeler3F
Sun Dec 06, 2020 6:59 pm
Forum: Polyprotic Acids & Bases
Topic: multiple deprotonations and sulfuric acid
Replies: 2
Views: 19

Re: multiple deprotonations and sulfuric acid

It means the Ka1 for H2SO4 is greater than one so the ratio between H+ and H2SO4 (at eq) is so large that the amount of H2SO4 is trivial. For normal polyprotic acids I cannot think of much importance since the following Ka values are so small the amount of H+ they contribute is also trivial. Polypro...
by IanWheeler3F
Sun Dec 06, 2020 6:52 pm
Forum: Polyprotic Acids & Bases
Topic: Textbook 6C.19
Replies: 7
Views: 60

Re: Textbook 6C.19

I like to think about it in terms of electronegativity, fluorine is THE most electronegative atom. It is extremely hard to contain it in its diatomic form F2 without it reacting. You will notice that some of the only compounds of noble gases are with fluorine. That is all to say is that when fluorin...
by IanWheeler3F
Sun Dec 06, 2020 6:28 pm
Forum: Calculating the pH of Salt Solutions
Topic: AlCl3 pH
Replies: 1
Views: 28

Re: AlCl3 pH

The three chlorides are "spectator" ions meaning they do not participate in the reaction so they are ignored. I remember learning this in Ap, so when metal cations are in water they always form a hydrated complex with a number of water molecules twice the value of their oxidation state. So...
by IanWheeler3F
Sun Dec 06, 2020 6:19 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Pka and Ka
Replies: 6
Views: 51

Re: Pka and Ka

pKa literally means "potenz of the acid dissociation constant," potenz is "power" in German which is where the p comes from. It essentially asks for the opposite of value of the exponent of Ka. pKa is used for buffers and choosing indicators, and it can predict pH as well which i...
by IanWheeler3F
Sun Dec 06, 2020 6:13 pm
Forum: Polyprotic Acids & Bases
Topic: Box 6E.1
Replies: 2
Views: 16

Re: Box 6E.1

I think he may just want us to realize not all acids are strong and not all have just one Ka value if they are polyprotic. I remember we had a longer list like that in high school but it was only used for reference during homework, and it also had Kb and pKb values. I honestly don't know why it is t...
by IanWheeler3F
Sun Dec 06, 2020 6:05 pm
Forum: Identifying Acidic & Basic Salts
Topic: Concept of pH
Replies: 10
Views: 46

Re: Concept of pH

Acidic and basic solutions are important because they are really prone to electron transfer, meaning they are very reactive. For example, bleaching works because it is very reactive with dyes and ruins the structure that gives dyes their color. pH is important because living organisms take advantage...
by IanWheeler3F
Sun Dec 06, 2020 5:50 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Sapling Week 10: #13 and #14
Replies: 2
Views: 33

Re: Sapling Week 10: #13 and #14

For weak bases and acids they exist in an equilibrium with an equilibrium constant Ka (acid dissociation constant). So only a certain amount of protons or hydroxide are dissociated out. This concentration determines the pH, the negative log of [H+] or [OH-]. pKa is the negative log of Ka which is al...
by IanWheeler3F
Sun Dec 06, 2020 5:26 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 6D.11
Replies: 1
Views: 23

Re: 6D.11

So for these you need to figure out where the cations and anions "came from" since salts are produced as the result of acid-base reactions. For example, KBr is formed when KOH and HBr react forming H20 and KBr. Now, we look at what the strength of these two acids and bases are. KOH is a st...
by IanWheeler3F
Sun Dec 06, 2020 5:13 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Sapling #10. How can you tell which solution has a higher pH?
Replies: 7
Views: 62

Re: Sapling #10. How can you tell which solution has a higher pH?

You have to first know which ones are strong acids and strong bases, these will be the highest and lowest pHs. Then, figure out which of those strong acids/bases gives off more H+ or OH-, Sr(OH)2 gives off 2 OH- so it is 'more' basic and has a higher pH. Then, figure out which are weak acids/bases a...
by IanWheeler3F
Sun Dec 06, 2020 5:05 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Equilibrium sign
Replies: 9
Views: 330

Re: Equilibrium sign

The Ka values of strong acids and bases are so large that it can be assumed that there is no back and forth between which species are present, there are just protons and anions.
by IanWheeler3F
Sun Dec 06, 2020 5:00 pm
Forum: Amphoteric Compounds
Topic: Amphoteric Compound Acid/Base Character
Replies: 4
Views: 13

Re: Amphoteric Compound Acid/Base Character

amphoteric is when it can act as either an acid or base, regardless of strength of the acid or base
by IanWheeler3F
Sun Dec 06, 2020 4:51 pm
Forum: Amphoteric Compounds
Topic: How to know if a molecule is amphoteric
Replies: 9
Views: 97

Re: How to know if a molecule is amphoteric

Im pretty sure HSO4- is amphoteric, it has a Ka value and can give up protons as well as accept them. Also hydroxide (OH-) is amphoteric since it can accept a proton to become HOH (H20) or give one up to become oxide (02-). There is also the difference between amphoteric and amphiprotic, amphoteric ...
by IanWheeler3F
Mon Nov 30, 2020 1:45 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: TM and coordination compounds
Replies: 2
Views: 48

Re: TM and coordination compounds

Water forms hydrates with a lot of compounds meaning it is acting as a lewis base and donating an electron pair. A well-known hydrate is epsom salts, which is magnesium sulfate. Water also forms complexes with other metals like sodium ions and aluminum ions when water dissolves them. I don't know ex...
by IanWheeler3F
Mon Nov 30, 2020 1:08 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligands
Replies: 9
Views: 71

Re: Ligands

Ligands do not have to bond only with transition metals, aqueous sodium ions (and other metal ions) form hydrated complexes with water.
by IanWheeler3F
Mon Nov 30, 2020 1:02 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: polydentate
Replies: 4
Views: 48

Re: polydentate

Polydentate are usually organic structures with ammine groups, which in english is a big carbon- net with a bunch of nitrogen groups, and the nitrogen groups are the ones that bond to the metal. They are usually abbreviated so if you see en, pn, dien, trien, EDTA then these are all polydentate. Then...
by IanWheeler3F
Mon Nov 30, 2020 12:43 pm
Forum: Naming
Topic: 9C.3 textbook problem
Replies: 3
Views: 54

Re: 9C.3 textbook problem

I think putting oxalato before aquo is part of an old naming system. I found this old chem textbook whose directions for naming coordination compounds says the ligands on the name go "negative, neutral, positive" which is consistent with putting a negative (oxalate) before a neutral (water...
by IanWheeler3F
Mon Nov 30, 2020 12:35 pm
Forum: Naming
Topic: Bis-, Tris-, etc
Replies: 6
Views: 26

Re: Bis-, Tris-, etc

An example is [Pt(en)2Cl2]Br2 whose name is: Dichlorobis(ethylenediamine)platinum(IV)
Another is the ion [Co(en)2(H20)2] 2+ with the name: Bis(ethylenediamine)diaquocobalt(II)
by IanWheeler3F
Sun Nov 22, 2020 9:50 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Acids/Bases
Replies: 7
Views: 83

Re: Acids/Bases

Like someone said about not needing to know this yet but, there are only 7 strong acids that dissolve completely into H+ and anions, and then there are only a few strong bases which are hydroxides of all group one elements and Calcium, Strontium, and Barium. Otherwise any other acid or base only par...
by IanWheeler3F
Sun Nov 22, 2020 9:39 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Hydrogen Bonding Confusion
Replies: 3
Views: 47

Re: Hydrogen Bonding Confusion

They didn't explain it well in the textbook but I was always taught hydrogen bonds are between: 1. A partially positively charged hydrogen that is covalently bonded to a F, O, or N (because hydrogen bonding is "Fon") 2. A lone pair on any F, O, or N This means that water (hydrogen attached...
by IanWheeler3F
Sun Nov 22, 2020 9:28 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Polarity from Lewis Structures
Replies: 6
Views: 28

Re: Polarity from Lewis Structures

We can look at electronegativities to see which atom has a higher electron density, and then you can draw dipole arrows which kinda look like this: +--->
the plus end is positive and the arrow end is negative, it will have a higher electron density
by IanWheeler3F
Sun Nov 22, 2020 9:26 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Molecular Shape of Large Molecules
Replies: 3
Views: 13

Re: Molecular Shape of Large Molecules

If you're looking at a lewis structure or organic shorthand you can also look at the dashes and bars for bonds to see "shape" of a molecule, since dashes denote a bond going "behind" the paper and bars denote bonds poking "out" of the page.
by IanWheeler3F
Sun Nov 22, 2020 9:23 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Seesaw Shape
Replies: 8
Views: 39

Re: Seesaw Shape

The axial atoms are in the most favorable positions because of repulsion and keeping the atoms the furthest apart they can possibly be, and then the two equatorial atoms must be in a bent shape since the electron pair repels them. In this shape all the atoms are the spread the furthest away from eac...
by IanWheeler3F
Sun Nov 15, 2020 8:40 pm
Forum: Dipole Moments
Topic: Dipoles vs Ions
Replies: 5
Views: 29

Re: Dipoles vs Ions

Like everyone is saying, the difference between the two is how electrons are shared, ionic completely moves the electron but dipoles unequally share them. But the way I like to think about unequal electron sharing in dipoles is the resonance structure. The bond in HF is a single bond where hydrogen ...
by IanWheeler3F
Sun Nov 15, 2020 8:31 pm
Forum: Dipole Moments
Topic: Strength of intermolecular forces
Replies: 3
Views: 46

Re: Strength of intermolecular forces

I think what it means is dipoles are only temporary and can merge to become neutral, so in the case of two dipoles when they are separated from each other the two dipoles stop reciprocating charge with one another. But a point charge (like an ion) is ALWAYS a point charge no matter how far away it i...
by IanWheeler3F
Sun Nov 15, 2020 8:24 pm
Forum: Dipole Moments
Topic: 3F.15 Question
Replies: 2
Views: 15

Re: 3F.15 Question

I know we haven't discussed structure yet but AsF5 has no net dipole whereas AsF3 does have a net dipole moment meaning it has partially charged ends. So AsF3 will act like a little magnet and be more difficult to separate leading to it needing more energy to break the dipole-dipole IMFs so it will ...
by IanWheeler3F
Sun Nov 15, 2020 8:14 pm
Forum: Dipole Moments
Topic: Hydrocarbons
Replies: 3
Views: 17

Re: Hydrocarbons

We usually say induced-dipole induced-dipole because the properties of hydrocarbons change very quickly as the number of carbons in a hydrocarbon increases. So like for methane there is only one carbon and four hydrogens meaning there are very few electrons leading to a very low attraction due to in...
by IanWheeler3F
Sun Nov 15, 2020 8:03 pm
Forum: Coordinate Covalent Bonds
Topic: Lewis Diagram
Replies: 5
Views: 58

Re: Lewis Diagram

One way you can "know" there is a coordinate covalent bond is when you see these brackets [ ] and a metal and a bunch of molecules/atoms all stuck together in a chemical formula. Like here's a random one: [Pt(NH3)3(Cl3)]Cl. I know the question was for lewis structures so when you see these...
by IanWheeler3F
Sun Nov 08, 2020 6:12 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal Charge
Replies: 4
Views: 59

Re: Formal Charge

This is a hard one but I guess it comes down to how far apart the charges are being distributed, like if there was a single bond between the 0 and -2 in one but a triple between the -1 and -1 then the charges on the -1 -1 are not only closer to zero but they are closer together, and it takes energy ...
by IanWheeler3F
Sun Nov 08, 2020 6:03 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Polarizable
Replies: 3
Views: 16

Re: Polarizable

To be highly polarizable means that a molecule has so many electrons that sometimes a high density of electrons can be found on just one side of the atom. This high density all one one side creates a very temporary moment of unusually high negative charge, which means the other side without all thes...
by IanWheeler3F
Sun Nov 08, 2020 5:53 pm
Forum: Resonance Structures
Topic: Identifying Delocalized Electrons
Replies: 2
Views: 32

Re: Identifying Delocalized Electrons

Also, and I know we don't talk a lot about d-block metals in this class, but when "identifying" delocalized electrons keep in mind that most of not all d-block metals do not keep the electrons in their outermost d-orbital very closely attached so they often move freely between themselves a...
by IanWheeler3F
Sun Nov 08, 2020 5:47 pm
Forum: Resonance Structures
Topic: delocalized electron energy
Replies: 3
Views: 25

Re: delocalized electron energy

I don't know if an electron has a lot of energy per se, other than kinetic energy, do you mean it would take less energy to remove a delocalized electron? Because I would imagine if an electron isn't associated with any one atom then it would take less energy to remove since it is less tightly held,...
by IanWheeler3F
Sun Nov 08, 2020 5:42 pm
Forum: Resonance Structures
Topic: Overall Structure of Ion - Sapling #4, W5
Replies: 3
Views: 24

Re: Overall Structure of Ion - Sapling #4, W5

Also you can find out which structure contributes the least by looking at experimental bond length. So if a molecule has three bonds and all three are determined to be the same at 155 picometers, but the single bond length would be 200pm and the double bond length would be 140pm, then you can probab...
by IanWheeler3F
Sun Oct 25, 2020 8:23 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Chromium and Copper
Replies: 5
Views: 46

Re: Chromium and Copper

This also hold for chromium and coppers entire groups, 6 and 11 respectively. And yeah the d-block is weird since electrons are more stable when "symmetrical" with one another meaning a full or half full outermost d-sub level is most stable.
by IanWheeler3F
Sun Oct 25, 2020 8:15 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 1E.5 electrons penetrating the nucleus
Replies: 1
Views: 18

Re: 1E.5 electrons penetrating the nucleus

I think its bc s-orbitals don't have nodal planes or weird orbital shapes that form around the nucleus like p, d, and f orbitals do. s-orbitals are an evenly distributed sphere that can get very close to the nucleus without touching it so since they're more likely to be closer to the nucleus they ca...
by IanWheeler3F
Sun Oct 25, 2020 8:06 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Advice for studying
Replies: 92
Views: 2030

Re: Advice for studying

For me I usually study in little bits rather than all at once or cram so I do one part of the textbook and its corresponding questions, and do a few sapling questions most days. And I also find videos online to be helpful if the textbook doesn't make sense
by IanWheeler3F
Sun Oct 25, 2020 8:02 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Silver Atom
Replies: 3
Views: 39

Re: Silver Atom

the entire group 11 follows the same pattern, and then there's another weird group, 6, that fills half of its d orbitals after taking one electron from the outermost s orbital (for chromium its 3d5 4s1) since it is more stable to fill half of the d orbitals, much like how it is more stable to fill a...
by IanWheeler3F
Sun Oct 25, 2020 7:53 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Effective Nuclear Charge
Replies: 2
Views: 15

Re: Effective Nuclear Charge

I think "effective nuclear charge" might mean the charges aren't balanced due to shielding and when charges aren't balanced one end of the atom has a different charge than the other leading the atom, despite its equal number of protons and electrons, to have charged ends
by IanWheeler3F
Sun Oct 18, 2020 7:25 pm
Forum: Properties of Light
Topic: energy level transfer
Replies: 7
Views: 36

Re: energy level transfer

what i understood was the energy given off going between any two n levels is E = -(hR)/(n^2) so as you change n levels near infinity you don't really change and distance and when you don't move you don't do work so the energy change is 0. Honestly I'm not 100% clear on it either since I don't fully ...
by IanWheeler3F
Sun Oct 18, 2020 7:19 pm
Forum: Properties of Light
Topic: Work Function
Replies: 3
Views: 46

Re: Work Function

The work function is like a threshold yeah, I don't know if theres a more "scientific" way to determine it but I got the impression it can be determined by doing the photoelectric experiment and using hv = p(Ke of electon) + (phi), and then solving for phi.
by IanWheeler3F
Sun Oct 18, 2020 7:14 pm
Forum: Properties of Light
Topic: Spectroscopy Question
Replies: 2
Views: 13

Re: Spectroscopy Question

the wavelength of the light is different because energy and frequency of light are directly proportional since E = hv, so when larger jumps are made in the Lyman series there is a larger energy change and therefore a higher of frequency of light is emitted, and UV light has a high frequency
by IanWheeler3F
Sun Oct 18, 2020 7:02 pm
Forum: Trends in The Periodic Table
Topic: electronegative of the elements in the periodic table
Replies: 4
Views: 68

Re: electronegative of the elements in the periodic table

Everything everyone said I agree with just metals in the "d" block (the middle) of the periodic table all have similar properties notwithstanding the group they are in. That is to say they don't act as consistent in groups as group 1, 2, 17, 18 that all act incredibly similar within their ...
by IanWheeler3F
Sun Oct 18, 2020 6:53 pm
Forum: Quantum Numbers and The H-Atom
Topic: Reading the Balmer and Lyman series model
Replies: 3
Views: 50

Re: Reading the Balmer and Lyman series model

if youre talking abt the model with the lines like n=1, n=2, etc then to read it you have to pay attention to the distance between the levels of n, its confusing but the distance between each level is not constant so the distance between n=1 and n=2 is much larger than the distance from n=3 to n=4, ...
by IanWheeler3F
Fri Oct 09, 2020 4:37 pm
Forum: Balancing Chemical Reactions
Topic: Combining Atoms
Replies: 7
Views: 135

Re: Combining Atoms

Also another thing about writing out molecular formulas from names is sometimes they'll say "cuprOUS oxide" or "cuprIC oxide" and the thing is a lot of metals have two really common oxidation states (charges) and putting -ous infers the metal has the lower charge whereas putting ...
by IanWheeler3F
Fri Oct 09, 2020 4:07 pm
Forum: Balancing Chemical Reactions
Topic: WK 1 Sapling #10
Replies: 7
Views: 87

Re: WK 1 Sapling #10

I think the bromine and magnesium are spectators? Like they don't play a meaningful part in the reaction and just end up as ions in solution and don't precipitate out (make a solid). And also this looks like an organic chem reaction so I don't think any of us understand exactly why it is the way it ...
by IanWheeler3F
Fri Oct 09, 2020 3:59 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Finding molar mass of sulfide of metal hydroxide? (E. 15)
Replies: 3
Views: 50

Re: Finding molar mass of sulfide of metal hydroxide? (E. 15)

Just be sure to remember the metal has a +2 charge and you need 2 sulfides
by IanWheeler3F
Fri Oct 09, 2020 3:50 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Molar Mass and Molecular Mass Difference?
Replies: 21
Views: 255

Re: Molar Mass and Molecular Mass Difference?

Adding on to the isotope comment, the reason carbon's amu is 12.011 and not 12 is because the 12.011amu is the average of the masses of all carbon isotopes, so while most carbon is 12amu, there is a smaller fraction of carbon in the universe that weights more (13amu and 14amu) so after dividing the ...
by IanWheeler3F
Fri Oct 09, 2020 3:42 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Exercise E.9
Replies: 6
Views: 133

Re: Exercise E.9

To answer the part of your question pertaining to why it is hydrated is: a lot of (if not all) metals often form these "coordination complexes" where they bond with certain elements and molecules and ions (most notably water, ammonia, halides, etc.) and since water is extra "sticky&qu...

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