Search found 61 matches

by MaggieHan1L
Sun Jan 19, 2020 5:43 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: 5J.5
Replies: 2
Views: 10

Re: 5J.5

When volume decreases, the reaction favors the side with less moles of gas.
by MaggieHan1L
Sun Jan 19, 2020 5:42 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: pKa
Replies: 13
Views: 21

Re: pKa

Lower pKa means a less negative Ka which means that there is a high amount of dissociation and thus a stronger acid.
by MaggieHan1L
Sun Jan 19, 2020 5:39 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5I 33
Replies: 2
Views: 10

Re: 5I 33

It's not a part of the problem. It's most likely put there to trick you. You don't need to know about the reactants since it is a solid and thus wouldn't go into calculations. Since you know the mass of CO2 then you know molarity of CO2 and molarity of NH3. CO2 would be equivalent to X and NH3 would...
by MaggieHan1L
Sun Jan 19, 2020 5:34 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Acids/Bases and Chemical Equilibrium
Replies: 2
Views: 12

Re: Acids/Bases and Chemical Equilibrium

Acids/Bases usually require a lot of ICE tables since weak acids/bases don't dissociate completely
by MaggieHan1L
Sun Jan 19, 2020 5:32 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: temperature change in reactions
Replies: 2
Views: 9

Re: temperature change in reactions

If a reaction is endothermic than it requires heat to get to the products so adding heat is favoring the products. If a reaction is exothermic, that is saying the same thing as the reverse reaction is endothermic so increasing temperature favors the reactants.
by MaggieHan1L
Sun Jan 12, 2020 12:25 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: When to do ice tables [ENDORSED]
Replies: 4
Views: 19

Re: When to do ice tables [ENDORSED]

A hint to do an ICE might be when you get only a few concentrations and you get K
by MaggieHan1L
Sun Jan 12, 2020 12:23 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: States of matter [ENDORSED]
Replies: 4
Views: 15

Re: States of matter [ENDORSED]

Solids and liquids have a basically constant concentration so it won't change K because it would just cancel out if you write it out.
by MaggieHan1L
Sun Jan 12, 2020 12:21 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Meaning of K [ENDORSED]
Replies: 4
Views: 23

Re: Meaning of K [ENDORSED]

K is the ratio of products and reactants. Things like increasing temperature and adding a catalyst speed up the rates.
by MaggieHan1L
Sun Jan 12, 2020 12:19 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Calculating K
Replies: 5
Views: 19

Re: Calculating K

If you included it since the concentration doesn't change, the liquid and solid would just cancel out.
by MaggieHan1L
Sun Jan 12, 2020 12:15 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kc vs. Kp [ENDORSED]
Replies: 4
Views: 26

Re: Kc vs. Kp [ENDORSED]

Yes when we see gas we assume Kp and when we see aqueous we assume Kc.
by MaggieHan1L
Sun Dec 08, 2019 11:33 pm
Forum: Naming
Topic: Cyanido
Replies: 2
Views: 35

Re: Cyanido

The rule is if it ends in ide it turns to ido
by MaggieHan1L
Sun Dec 08, 2019 11:31 pm
Forum: Conjugate Acids & Bases
Topic: Neutralization Equations
Replies: 3
Views: 52

Re: Neutralization Equations

neutralization is usually strong acids and bases I think
by MaggieHan1L
Sun Dec 08, 2019 11:28 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 6B.1
Replies: 2
Views: 43

Re: 6B.1

That's the only way to get a number without knowing the concentrations. Since it's -log (0.12H+)-(-log (H+), you can change it to log (H+)-(log 0.12(H+)) and thus you can take log 1/0.12 since the H+ will cancel.
by MaggieHan1L
Sun Dec 08, 2019 11:11 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: common acids and bases
Replies: 4
Views: 39

Re: common acids and bases

My TA mentioned that usually the organic molecules were the weak ones.
by MaggieHan1L
Sun Dec 08, 2019 11:09 pm
Forum: Polyprotic Acids & Bases
Topic: Amphiprotic vs Amphoteric
Replies: 6
Views: 64

Re: Amphiprotic vs Amphoteric

Amphiprotic is always amphoteric but amphoteric is not always amphiprotic.
by MaggieHan1L
Sun Dec 01, 2019 3:31 pm
Forum: Bronsted Acids & Bases
Topic: Net Ionic Equations
Replies: 3
Views: 28

Re: Net Ionic Equations

It depends on whether or not they dissociate completely in water.
by MaggieHan1L
Sun Dec 01, 2019 3:27 pm
Forum: Amphoteric Compounds
Topic: 6A.11
Replies: 2
Views: 21

Re: 6A.11

I think the easiest way when you're told that the molecule is amphoteric is to just add a proton and minus a proton. So you would end up with PO4 (3-) and H2PO4 for HPO4.
by MaggieHan1L
Sun Dec 01, 2019 3:22 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: [H3O+] and [OH-]
Replies: 3
Views: 34

Re: [H3O+] and [OH-]

If you want to calculate directly [H3O+][OH-]=10^-14.
by MaggieHan1L
Sun Dec 01, 2019 3:19 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Acid Strength
Replies: 3
Views: 30

Re: Acid Strength

My TA explained it as those molecules having more resonance usually and thus without the proton they are more stable so they are more willing to be dissociated. At least this is how I understood it.
by MaggieHan1L
Sun Dec 01, 2019 3:18 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Strong vs Weak Acids
Replies: 7
Views: 34

Re: Strong vs Weak Acids

Usually acids that have an atom which is more electronegative will be stronger
by MaggieHan1L
Sun Nov 24, 2019 4:33 pm
Forum: Biological Examples
Topic: Transition metals and their biological importance
Replies: 2
Views: 17

Re: Transition metals and their biological importance

I don't think you actually have to memorize them because he probably just wanted to show us the importance of these metals.
by MaggieHan1L
Sun Nov 24, 2019 4:31 pm
Forum: Naming
Topic: #9C3 d
Replies: 2
Views: 47

Re: #9C3 d

Doesn't it have to do with alphabetical order?
by MaggieHan1L
Sun Nov 24, 2019 4:28 pm
Forum: Bronsted Acids & Bases
Topic: Acid Naming
Replies: 2
Views: 32

Re: Acid Naming

Yes cation before anion
by MaggieHan1L
Sun Nov 24, 2019 4:27 pm
Forum: Naming
Topic: Coordination number
Replies: 7
Views: 33

Re: Coordination number

Coordination numbers depend on the number of bonds.
by MaggieHan1L
Sun Nov 24, 2019 4:24 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: transition metals
Replies: 2
Views: 14

Re: transition metals

You calculate oxidation numbers based on charges of the rest of the compound.
by MaggieHan1L
Sun Nov 17, 2019 2:18 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR notation
Replies: 8
Views: 59

Re: VSEPR notation

A for the central atom. X for the bonded atoms. E for the lone pairs.
by MaggieHan1L
Sun Nov 17, 2019 2:15 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Seesaw
Replies: 23
Views: 124

Re: Seesaw

I don't know if the angle has a difference that is significant. 90 and 120 should be fine.
by MaggieHan1L
Sun Nov 17, 2019 11:20 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Shapes We Are Expected to Know
Replies: 6
Views: 38

Re: Shapes We Are Expected to Know

He said that the ones we discussed in class in Friday we need to know and we also need to know Monday's lecture.
by MaggieHan1L
Sun Nov 17, 2019 11:19 am
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR Model
Replies: 5
Views: 23

Re: VSEPR Model

Electron focuses more on how the electrons are placed and bonding than molecular. So molecular tends to be more general focusing on regions of electron density while electron focuses on lone pairs and where they are placed because of the electron electron repulsion.
by MaggieHan1L
Sun Nov 17, 2019 11:16 am
Forum: Determining Molecular Shape (VSEPR)
Topic: identifying pi & sigma bonds
Replies: 3
Views: 37

Re: identifying pi & sigma bonds

I think he's going to cover this more in depth on Monday
by MaggieHan1L
Sun Nov 10, 2019 5:20 pm
Forum: Dipole Moments
Topic: 3F. 5
Replies: 2
Views: 31

Re: 3F. 5

H bond needs a hydrogen bonded to a highly electronegative atom such as F, O, and N.
by MaggieHan1L
Sun Nov 10, 2019 5:06 pm
Forum: Electronegativity
Topic: Ionization Energy vs. Electronegativity
Replies: 9
Views: 44

Re: Ionization Energy vs. Electronegativity

Think of ionization energy as what it takes to make an anion and electronegativity is how badly it wants to be negative. That's how I remember it. Don't know if that helps
by MaggieHan1L
Sun Nov 10, 2019 5:02 pm
Forum: Bond Lengths & Energies
Topic: Interaction Potential Energy Formula
Replies: 2
Views: 24

Re: Interaction Potential Energy Formula

You just have to be aware of the proportionality and that r is to the power of 6 so it has a pretty big impact.
by MaggieHan1L
Sun Nov 10, 2019 4:51 pm
Forum: Bond Lengths & Energies
Topic: London Forces
Replies: 6
Views: 42

Re: London Forces

London forces are created when there are slight e density fluctuations and these are just in all compounds
by MaggieHan1L
Sun Nov 10, 2019 4:42 pm
Forum: Bond Lengths & Energies
Topic: Bond strength
Replies: 4
Views: 28

Re: Bond strength

It also has to do with size. Larger atoms results in longer bond length and a weaker bond.
by MaggieHan1L
Sun Nov 03, 2019 2:54 pm
Forum: Dipole Moments
Topic: Midterm
Replies: 8
Views: 90

Re: Midterm

Friday's lecture. The last slide was going to be on it but then we got class canceled on Monday.
by MaggieHan1L
Sun Nov 03, 2019 2:52 pm
Forum: Resonance Structures
Topic: Defining Resonance Structures
Replies: 3
Views: 20

Re: Defining Resonance Structures

I think that formal charge also comes into play.
by MaggieHan1L
Sun Nov 03, 2019 2:45 pm
Forum: Octet Exceptions
Topic: Expanded Valence Shells
Replies: 2
Views: 18

Re: Expanded Valence Shells

My TA said that it has to do with energies and hybridizations. An easy way is just to think about it in terms of being able to draw from the d subshells which only start when n=3
by MaggieHan1L
Sun Nov 03, 2019 2:43 pm
Forum: Octet Exceptions
Topic: What are radicals
Replies: 7
Views: 36

Re: What are radicals

Because they are exceptions to the octet rule, they are highly reactive and unstable. They're very dangerous because they can modify DNA and other biologic molecules. They usually don't remain in that state for long.
by MaggieHan1L
Sun Nov 03, 2019 2:29 pm
Forum: Ionic & Covalent Bonds
Topic: Relationship with Polarity
Replies: 3
Views: 28

Re: Relationship with Polarity

You can think of bigger polarity as one element wanting and pulling on electrons more. Thus ionic is just when there is such a big difference that one element "gets" the electron instead of sharing it.
by MaggieHan1L
Sun Oct 27, 2019 1:52 pm
Forum: Formal Charge and Oxidation Numbers
Topic: 2B. 23
Replies: 2
Views: 33

Re: 2B. 23

The preferred formal charge is 0. When he gave the example of sulphate SO4, the lewis structure was technically correct but the formal charges weren't ideal. We use formal charge to give us better lewis dot structures. When you're drawing lewis dot structures and you can't get all of the formal char...
by MaggieHan1L
Sun Oct 27, 2019 1:47 pm
Forum: Lewis Structures
Topic: Bond Lengths
Replies: 2
Views: 29

Re: Bond Lengths

When he was talking about Benzene, he was pointing out that the bonds are neither the length of a single or a double bond because of the resonance. The bond lengths depend based on the elements and what type of bond it is. For example N-O in nitrate was 1.24 A while C-C in benzene was 1.39 A.
by MaggieHan1L
Sun Oct 27, 2019 1:43 pm
Forum: Ionic & Covalent Bonds
Topic: P, Cl, and S octet tule exceptions
Replies: 4
Views: 27

Re: P, Cl, and S octet tule exceptions

Other elements such as N and O and F can't because they are in N=2 meaning they only have access to s and p and can only form an octet. In general just remember n=3 as what makes it an exception.
by MaggieHan1L
Sun Oct 27, 2019 1:41 pm
Forum: Ionic & Covalent Bonds
Topic: 2.A.17
Replies: 3
Views: 33

Re: 2.A.17

Positive means that they lost electrons so that's why you subtract from the ground state. If they were negative you would add because they gained electrons.
by MaggieHan1L
Sun Oct 27, 2019 1:39 pm
Forum: Ionic & Covalent Bonds
Topic: 2A.15
Replies: 4
Views: 30

Re: 2A.15

Losing 1 electron in the p orbital doesn't lead to an octet because there are still 2 electrons in the s orbital
by MaggieHan1L
Sun Oct 20, 2019 11:02 am
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Heinsberg Uncertainty Equation Post-Module Question #18
Replies: 2
Views: 30

Re: Heinsberg Uncertainty Equation Post-Module Question #18

The uncertainty of the electron would be diameter and you used radius.
by MaggieHan1L
Sun Oct 20, 2019 10:59 am
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: 1.B #15
Replies: 2
Views: 32

Re: 1.B #15

The part where they say "Model the atom as a one-dimensional box with a length equal to the diameter of the actual atom." just means make delta x = to diameter. That's basically what you always do when you see diameter and uncertainty. Then you get speed by changing delta p into m times de...
by MaggieHan1L
Sun Oct 20, 2019 10:54 am
Forum: Properties of Electrons
Topic: Shared Electrons
Replies: 4
Views: 40

Re: Shared Electrons

It has to do with electron repulsions. The electrons make sure every orbital has one electron first because two electrons in the orbital has repulsions. At least that's what I remember from high school.
by MaggieHan1L
Sun Oct 20, 2019 10:52 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: p- orbital
Replies: 3
Views: 25

Re: p- orbital

Hung Indy Bui 3H is right, it all depends on how you label it and look at it. You can go any way you want.
by MaggieHan1L
Sun Oct 20, 2019 10:37 am
Forum: *Shrodinger Equation
Topic: Shrodinger Equation
Replies: 3
Views: 31

Re: Shrodinger Equation

Dr. Lavelle said he wouldn't go into the deriving of the equation because that was out of the scope of the class.
by MaggieHan1L
Sat Oct 12, 2019 1:04 pm
Forum: Properties of Electrons
Topic: Mass of Electron in De Broglie Equation
Replies: 4
Views: 30

Re: Mass of Electron in De Broglie Equation

Even though we didn't need it, I'm pretty sure on the last test Dr. Lavelle printed out the mass of an electron on the formula sheet
by MaggieHan1L
Sat Oct 12, 2019 1:02 pm
Forum: Properties of Electrons
Topic: Clarification on particle vs wave properties
Replies: 3
Views: 27

Re: Clarification on particle vs wave properties

I think that many things have wavelike properties but they aren't really detectable such as when they are smaller than 10^-15 and then you say they have more particle like properties
by MaggieHan1L
Sat Oct 12, 2019 1:00 pm
Forum: Properties of Electrons
Topic: Circular Standing Wave
Replies: 4
Views: 45

Re: Circular Standing Wave

Everything is quantized. It's not like a normal equation where you can plug in any number. There are only specific energies.
by MaggieHan1L
Sat Oct 12, 2019 12:58 pm
Forum: Administrative Questions and Class Announcements
Topic: Week 2 Homework Problems [ENDORSED]
Replies: 67
Views: 1592

Re: Week 2 Homework Problems [ENDORSED]

For week 3, we definitely have to do quantum.
by MaggieHan1L
Sat Oct 12, 2019 12:55 pm
Forum: Limiting Reactant Calculations
Topic: Showing Work for Limiting Reactant Calculations on Tests [ENDORSED]
Replies: 68
Views: 1587

Re: Showing Work for Limiting Reactant Calculations on Tests [ENDORSED]

Showing your work can also make it easier for you to double check your answers too!
by MaggieHan1L
Sat Oct 12, 2019 12:54 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Rydberg equation [ENDORSED]
Replies: 73
Views: 1617

Re: Rydberg equation [ENDORSED]

The rydberg equation I think is just an equation that combines a few steps of the Einitial - Efinal method.
by MaggieHan1L
Wed Oct 02, 2019 10:46 pm
Forum: Empirical & Molecular Formulas
Topic: Empirical and Molecular Formula Masses
Replies: 5
Views: 62

Re: Empirical and Molecular Formula Masses

Empirical formula is the lowest ratio so molecular formula should not be greater than the empirical.
by MaggieHan1L
Wed Oct 02, 2019 10:39 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Molar Mass
Replies: 10
Views: 87

Re: Molar Mass

For some problems where you have to find the molar mass of a sample with a lot of isotopes just multiply the isotope percentage by the isotope weight and add all of them together.
by MaggieHan1L
Wed Oct 02, 2019 10:34 pm
Forum: Balancing Chemical Reactions
Topic: Combustion Reaction Notation
Replies: 6
Views: 71

Re: Combustion Reaction Notation

One thing we talked about today in discussion is that when you see oxidized that also means that it is combustion. Thought that would be useful in decoding problems.
by MaggieHan1L
Wed Oct 02, 2019 10:31 pm
Forum: Limiting Reactant Calculations
Topic: limiting reactant
Replies: 5
Views: 77

Re: limiting reactant

One thing that stuck with me throughout high school chemistry is the mole tunnel. If you're having trouble just always remember grams to moles to moles to grams.
by MaggieHan1L
Wed Oct 02, 2019 10:29 pm
Forum: Administrative Questions and Class Announcements
Topic: Advice from a Medical Student - Part II [ENDORSED]
Replies: 130
Views: 2947

Re: Advice from a Medical Student - Part II [ENDORSED]

Thanks so much for taking the time to help out all of us who are so clueless. You gave such great and meaningful advice.

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