Search found 68 matches

by Sanjana Borle 2K
Sat Jan 18, 2020 3:22 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q < K
Replies: 16
Views: 40

Re: Q < K

If Q is less than K, then it means that there are more reactants than products when compared to equilibrium, so more products need to be formed.
by Sanjana Borle 2K
Sat Jan 18, 2020 3:20 pm
Forum: Administrative Questions and Class Announcements
Topic: Study Guide Test One
Replies: 17
Views: 66

Re: Study Guide Test One

Your best resources are probably the 2 Outlines as well as the Peer Learning and Step Up sessions.
by Sanjana Borle 2K
Sat Jan 18, 2020 3:09 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: ICE and quadratic formula
Replies: 11
Views: 29

Re: ICE and quadratic formula

If the initial concentration (such as 0.1-x) is small enough, then you can "take away" the x from the bottom ONLY since it is probably a small number, but this is just to make calculations easier. Technically it's not mathematically correct but the difference if you used the quadratic form...
by Sanjana Borle 2K
Sat Jan 18, 2020 3:06 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: ICE Tables
Replies: 3
Views: 25

Re: ICE Tables

Yes, generally an ice table is used if you know initial concentrations, and the K value. I dont think we have seen many other variations of this.
by Sanjana Borle 2K
Sat Jan 18, 2020 3:03 pm
Forum: Ideal Gases
Topic: Solids and Liquids [ENDORSED]
Replies: 10
Views: 61

Re: Solids and Liquids [ENDORSED]

Also for solids and liquids, pressure does not affect them, in other words they can't be compressed further, whereas gases can.
by Sanjana Borle 2K
Sun Jan 12, 2020 6:25 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K and Q
Replies: 10
Views: 25

Re: K and Q

If you compare Q to K, you can determine whether the reaction is going go to in the forward or reverse reaction to reach equilibrium.
by Sanjana Borle 2K
Sun Jan 12, 2020 6:24 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: memorization
Replies: 12
Views: 35

Re: memorization

Im not sure but I believe we might have to, since an equation sheet and periodic table is all we get.
by Sanjana Borle 2K
Sun Jan 12, 2020 2:12 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: 5J:5d
Replies: 2
Views: 16

Re: 5J:1d

As we learned in class, change in pressure generally does not change state of equlibrium.
by Sanjana Borle 2K
Sun Jan 12, 2020 2:10 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Homework 5G.1 Help
Replies: 3
Views: 16

Re: Homework 5G.1 Help

Essentially, because the reaction wants to reach equilibrium again after you add more reactant, that reactant will go through the reaction to form the product and the reaction will move forward, causing more product to form till it reaches equilibrium again.
by Sanjana Borle 2K
Sun Jan 12, 2020 2:08 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kc vs Kp
Replies: 10
Views: 22

Re: Kc vs Kp

Kc and Kp eventually lead to the same conclusion, it's just that Kc uses concentration and Kp uses pressure.
by Sanjana Borle 2K
Sat Dec 07, 2019 1:12 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: polarity of dichloromethane
Replies: 3
Views: 25

Re: polarity of dichloromethane

Unless all four surrounding molecules are the same, all tetrahedral molecules are polar.
by Sanjana Borle 2K
Sat Dec 07, 2019 12:28 pm
Forum: Lewis Acids & Bases
Topic: Problem 6.13 Textbook, boric acid
Replies: 1
Views: 23

Problem 6.13 Textbook, boric acid

Can someone explain why boric acid is a Lewis acid and an electron pair acceptor? Also does this mean that the conjugate base of boric acid is not stable since boric acid is a weak acid?
by Sanjana Borle 2K
Sat Dec 07, 2019 9:56 am
Forum: Determining Molecular Shape (VSEPR)
Topic: polarity of dichloromethane
Replies: 3
Views: 25

Re: polarity of dichloromethane

Since the structure of this molecule is tetrahedral, it is not the same that it looks when drawn as a 2 d Lewis structure. Essentially a tetrahedral structure can be rotated in different ways that is not accurately depicted in a 2 d structure, so if the H's and Cl's were opposite each other the mole...
by Sanjana Borle 2K
Sat Dec 07, 2019 9:53 am
Forum: Naming
Topic: "Cyano" vs. "Cyanido"
Replies: 1
Views: 21

Re: "Cyano" vs. "Cyanido"

"Cyano" is the conventional way of naming whereas "cyanido" is the new IUPAC way of naming. I believe that Lavelle accepts both, but uses the conventional way in all his examples. They both mean the same thing and either one is acceptable.
by Sanjana Borle 2K
Fri Dec 06, 2019 5:37 pm
Forum: Naming
Topic: cyano v. cyanido
Replies: 4
Views: 32

Re: cyano v. cyanido

cyano and cynanido essentially mean the same thing; I believe Lavelle accepts both on his tests, but uses the cyano. For more information refer to the Coordination Compounds pdf on his Chem 14A website.
by Sanjana Borle 2K
Fri Dec 06, 2019 2:04 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: polarizability
Replies: 4
Views: 34

Re: polarizability

Molecules with just London Dispersion forces do not have polarizability, as they are nonpolar. These forces are present in all molecules, even nonpolar ones.
by Sanjana Borle 2K
Fri Dec 06, 2019 11:36 am
Forum: Lewis Structures
Topic: Cl as a central atom
Replies: 3
Views: 47

Cl as a central atom

If Cl were to be a central atom in a molecule and there four surrounding atoms, would it be wrong to have 3 double bonds and a single bond in the molecule? Since in that case the formal charge of Cl is zero and it can expand its octet, would this technically be correct or 14 electrons too much?
by Sanjana Borle 2K
Fri Dec 06, 2019 11:34 am
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Identifying electron donors vs electron withdrawers (6C 21)
Replies: 1
Views: 25

Re: Identifying electron donors vs electron withdrawers (6C 21)

Basically electronegativity determines the electron withdrawing ability of atoms in a molecule, and therefore its acidity. So for the CH3 vs CCl3 example, since Cl is more electronegative, the Cl atoms pull the e- density closer to themselves, making the H easier to detach.
by Sanjana Borle 2K
Fri Dec 06, 2019 11:18 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligand Definition
Replies: 4
Views: 18

Re: Ligand Definition

A ligand is a molecule that attaches to a metal cation to form a coordination compound. A ligand can be a mono or poly dentate, which means it "bites" to the metal in one place or in multiple places. This depends on the structure and flexibility of the ligand.
by Sanjana Borle 2K
Fri Dec 06, 2019 11:17 am
Forum: Administrative Questions and Class Announcements
Topic: Curving in Chem 14A
Replies: 7
Views: 147

Re: Curving in Chem 14A

Nothing has been curved yet, but I believe that in the past Dr. Lavelle has curved the final grades of the class.
by Sanjana Borle 2K
Fri Dec 06, 2019 11:15 am
Forum: Bronsted Acids & Bases
Topic: Lewis vs Bronsted
Replies: 3
Views: 17

Re: Lewis vs Bronsted

The general trend is that acids like to become more negative and bases like to become more positive. Therefore, an acid in the Lewis definition is an electron pair acceptor and in a Bronsted definition a proton donor, and a base in the Lewis definition is an e- pair donor and a proton acceptor in th...
by Sanjana Borle 2K
Fri Dec 06, 2019 11:13 am
Forum: Biological Examples
Topic: Cisplatin H2O
Replies: 2
Views: 30

Re: Cisplatin H2O

I think the most we will have to know about cisplatin is how to draw it and why it is used as a chemotherapy drug whereas trans platin is not.
by Sanjana Borle 2K
Thu Dec 05, 2019 4:17 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: EDTA
Replies: 3
Views: 47

Re: EDTA

Also I believe that the singly bonded oxygens and the nitrogens have electron lone pairs that can form coordinate covalent bonds with said metal, so it chelates and binds to metals.
by Sanjana Borle 2K
Thu Dec 05, 2019 4:12 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Content of the final
Replies: 10
Views: 131

Re: Content of the final

We do not need to know about bond order; it helps to refer to the outline to see what exactly in the book we covered.
by Sanjana Borle 2K
Wed Dec 04, 2019 9:37 pm
Forum: Lewis Acids & Bases
Topic: HCl and HI
Replies: 10
Views: 42

Re: HCl and HI

Is there a periodic trend in terms of this? Does this mean that HF is the weakest acid, then HCl, then HBr, then HI?
by Sanjana Borle 2K
Wed Dec 04, 2019 9:36 pm
Forum: Polyprotic Acids & Bases
Topic: Ka value
Replies: 5
Views: 39

Re: Ka value

Does Ka 3 mean Ka1 plus Ka2? Is is the overall Ka for the reaction?
by Sanjana Borle 2K
Wed Dec 04, 2019 8:49 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Chelate
Replies: 5
Views: 38

Re: Chelate

I thought we use bis tris etc when naming multiple of the same polydentate? or is this the same thing?
by Sanjana Borle 2K
Wed Dec 04, 2019 8:47 pm
Forum: Identifying Acidic & Basic Salts
Topic: Lecture
Replies: 3
Views: 25

Re: Lecture

Since Cl- has a octet, it will not have an affinity to other ions or water so it won't affect the pH
by Sanjana Borle 2K
Wed Dec 04, 2019 8:46 pm
Forum: Naming
Topic: "Ferrate"
Replies: 14
Views: 108

Re: "Ferrate"

I think the one other exception we would need to know is for copper; it has a latin prefix of "cupr"
by Sanjana Borle 2K
Wed Dec 04, 2019 8:44 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordinate Compounds
Replies: 3
Views: 20

Re: Coordinate Compounds

I think we also need to know how to name them, as discussed in class.
by Sanjana Borle 2K
Wed Dec 04, 2019 2:45 pm
Forum: Biological Examples
Topic: Cisplatin
Replies: 6
Views: 45

Re: Cisplatin

I think we do, because he talked about the different structures that coordination compounds can have, like tetrahedral, octahedral, square planar.
by Sanjana Borle 2K
Wed Dec 04, 2019 2:41 pm
Forum: Naming
Topic: Naming for Hydrocarbons
Replies: 2
Views: 21

Re: Naming for Hydrocarbons

I believe we also need to know what a carboxyl group looks like, as well as other structurs we learned such as benzene or ethene.
by Sanjana Borle 2K
Wed Dec 04, 2019 2:41 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: coordination number
Replies: 3
Views: 25

Re: coordination number

Coordination number is simply the number of bonds formed.
by Sanjana Borle 2K
Wed Dec 04, 2019 2:39 pm
Forum: Biological Examples
Topic: Cisplatin
Replies: 6
Views: 45

Re: Cisplatin

Why is ciplatin square planar and not tetrahedral?
by Sanjana Borle 2K
Wed Dec 04, 2019 2:37 pm
Forum: Naming
Topic: Naming Acids/ Bases
Replies: 4
Views: 25

Re: Naming Acids/ Bases

I believe the -ic vs -ous depends on the composition of the anion. For nitric acid it is produced when a H+ bonds to the nitrate anion, and for nitrous acid it is produced when an H+ bonds to a nitrite anion. In general, an "ate" anion corresponds to an "ic" acid, and an "it...
by Sanjana Borle 2K
Sun Dec 01, 2019 9:33 pm
Forum: Lewis Acids & Bases
Topic: Final
Replies: 4
Views: 19

Re: Final

I'm not sure, but I'm guessing so; we have already been tested on everything else. This would be a good question for Dr. Lavelle or any of the TAs
by Sanjana Borle 2K
Sun Dec 01, 2019 9:31 pm
Forum: Conjugate Acids & Bases
Topic: the conjugate seesaw
Replies: 5
Views: 39

Re: the conjugate seesaw

In more detail, a conjugate base is produced when an acid donates a proton, and a conjugate acid is produced when a base accepts a proton.
by Sanjana Borle 2K
Sun Dec 01, 2019 9:30 pm
Forum: Student Social/Study Group
Topic: Final
Replies: 3
Views: 26

Re: Final

i think the final will have two more questions than the midterm, i believe it is similarly structured.
by Sanjana Borle 2K
Sun Dec 01, 2019 9:28 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Notes
Replies: 3
Views: 20

Re: Notes

Does this mean that we will be covering all new material up until Friday?
by Sanjana Borle 2K
Sun Dec 01, 2019 9:27 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: AXE formula
Replies: 32
Views: 1559

Re: AXE formula

The best way is to know the chart and which shape corresponds with which AXE formula.
by Sanjana Borle 2K
Sun Nov 24, 2019 5:17 pm
Forum: Naming
Topic: using brackets
Replies: 5
Views: 24

Re: using brackets

The brackets are what is inside the coordination sphere, which can be determined by the shape of the molecule.
by Sanjana Borle 2K
Sun Nov 24, 2019 5:14 pm
Forum: Electronegativity
Topic: Electronegativity
Replies: 12
Views: 74

Re: Electronegativity

If a atom has a very high electronegativity, it will pull on the electrons more and therefore form a stronger bond.
by Sanjana Borle 2K
Sun Nov 24, 2019 5:13 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Dipole Moment?
Replies: 4
Views: 22

Re: Dipole Moment?

So the shape of an atom will help you determine whether the dipole moments cancel out, and therefore whether the molecule is polar or nonpolar. You need to know the 3D geometry because there are some molecules that can be drawn in a Lewis structure to look "symetrical" but are actually not...
by Sanjana Borle 2K
Sun Nov 24, 2019 5:10 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: AXE Format
Replies: 34
Views: 121

Re: AXE Format

You do not have to write a subscript if it is just 1, it's like math.
by Sanjana Borle 2K
Sun Nov 24, 2019 5:09 pm
Forum: Lewis Acids & Bases
Topic: Lewis and Bronsted
Replies: 5
Views: 32

Re: Lewis and Bronsted

A lewis acid is an electron pair acceptor and a Lewis base lends an electron pair. The bronsted definition is that an acid is a proton donor and a base is a proton acceptor.
by Sanjana Borle 2K
Sun Nov 24, 2019 5:05 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Seesaw
Replies: 23
Views: 124

Re: Seesaw

Since there is a lone pair that replaces the atom in a trigonal bipyramidal, it "pushes" on the other atoms and causes their bond angles to decrease.
by Sanjana Borle 2K
Mon Nov 11, 2019 6:40 pm
Forum: Sigma & Pi Bonds
Topic: Sigma & Pi Bonds
Replies: 4
Views: 42

Re: Sigma & Pi Bonds

I believe they will be covered after the midterm.
by Sanjana Borle 2K
Mon Nov 11, 2019 6:39 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal charge
Replies: 16
Views: 68

Re: Formal charge

The second best option is to make sure that the more electronegative atom has a negative charge, and vice versa. this is considered the correct lewis structure.
by Sanjana Borle 2K
Sun Oct 27, 2019 8:33 pm
Forum: Octet Exceptions
Topic: Exceptions
Replies: 10
Views: 434

Re: Exceptions

Not only are some elements in the d block exceptions to the octet rule, so are the first four elements (hydrogen, Beryllium, Helium, and Lithium.
by Sanjana Borle 2K
Sun Oct 27, 2019 8:32 pm
Forum: Ionic & Covalent Bonds
Topic: Metalloids
Replies: 5
Views: 34

Re: Metalloids

Adding on to that, since metalloids neither have "too many" or "too little" valence electrons as can be seen by where they are placed in the periodic table, they can go either way and lose electrons or gain electrons. Hence, they are called metalloids.
by Sanjana Borle 2K
Sun Oct 27, 2019 8:30 pm
Forum: Resonance Structures
Topic: Formal Charge
Replies: 5
Views: 39

Re: Formal Charge

No, I believe not. Informal charges do not exist.
by Sanjana Borle 2K
Sun Oct 27, 2019 8:29 pm
Forum: Ionic & Covalent Bonds
Topic: Double bond placement
Replies: 15
Views: 89

Re: Double bond placement

Due to the concept of resonance, technically double and triple bonds can be anywhere as long as the satisfy the octet rule. Just make sure to count up all the electrons before you place the double and triple bonds in a certain location
by Sanjana Borle 2K
Sun Oct 27, 2019 8:26 pm
Forum: Lewis Structures
Topic: Drawing Lewis Structures
Replies: 3
Views: 21

Re: Drawing Lewis Structures

For me it really helps to count up all the total electrons in the structure and see if it matches my Lewis structure to check my work. It also helps for me to draw the atom in the center, which is the one with the least ionization energy, first so that I can draw everything around it after.
by Sanjana Borle 2K
Sat Oct 19, 2019 12:33 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Same spin
Replies: 10
Views: 71

Re: Same spin

Same spin means that the electrons spin in the same direction (parallel to each other) and have the same quantum number (1/2 or -1/2). According to Hund's rule all electrons that are unpaired in an orbital will have the same, or parallel spin, but if there is more electrons and it requires pairing u...
by Sanjana Borle 2K
Sat Oct 19, 2019 12:30 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: how to prepare
Replies: 22
Views: 138

Re: how to prepare

It would probably be really helpful to go to the step up sessions, since those start from the beginning and once you feel more comfortable you can go to the drop in ones. I also wouldnt stress about memorizing formulas because many will be provided but its important to know units (eg use kg and not ...
by Sanjana Borle 2K
Sat Oct 19, 2019 12:27 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Spin State
Replies: 6
Views: 51

Re: Spin State

I am not sure why the 1/2 is there for the spin quantum number but it may be because the other quantum numbers are integers
by Sanjana Borle 2K
Thu Oct 17, 2019 12:31 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Orbitals
Replies: 4
Views: 36

Re: Orbitals

if n is 2, l is 1, and ml is -1 then the electron is in -2px state because the n number corresponds to number of orbital and l corresponds to the fact that its a p orbital, and as mentioned above the -1 corresponds to the x axis. It is true that the orientation is arbitrary but the ml number tells u...
by Sanjana Borle 2K
Thu Oct 17, 2019 12:28 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: 1D #11
Replies: 3
Views: 39

Re: 1D #11

Another way to do this is match the letters spdf to the l numbers: 0 is s, 1 is p, 2 is d, and 3 is f. As mentioned in class the number of orbitals for s,p,d,f is 1,3,5,7 respectively.
by Sanjana Borle 2K
Sun Oct 13, 2019 11:16 am
Forum: DeBroglie Equation
Topic: When to use DeBroglie Equation
Replies: 16
Views: 147

Re: When to use DeBroglie Equation

You can't use the DeBroglie equation in terms of light because the light equation involves the constant C which is the speed of light, so the EM equations cannot be used for any particle either (doesn't work either way). The DeBroglie equation works only for particles which have wavelike properties.
by Sanjana Borle 2K
Sun Oct 13, 2019 11:14 am
Forum: Properties of Light
Topic: Wave Properties of electrons
Replies: 7
Views: 60

Re: Wave Properties of electrons

Diffraction is basically when the light passes through a small slit/opening and causes different kinds of patterns. These patterns involve constructive or destructive interference. In constructive interference the amplitudes of two(or more) waves "add up" causing the amplitude to increase ...
by Sanjana Borle 2K
Sat Oct 12, 2019 3:35 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Photoelectric Effect
Replies: 4
Views: 60

Re: Photoelectric Effect

Dr. Lavelle emphasized in lecture that intensity of the light did not matter when it came to exciting the electron because it only increased the amplitude, not changing the wavelength or frequency. But when other frequencies are used, they do have the potential to remove an electron from the surface.
by Sanjana Borle 2K
Sat Oct 12, 2019 2:39 pm
Forum: Properties of Electrons
Topic: Multi-Electron Systems
Replies: 4
Views: 28

Re: Multi-Electron Systems

I believe the Bohr model can be used for any one-electron system, however since hydrogen is the most common it is applied to a hydrogen atom. Technically other elements can have one electron but none of them except hydrogen will be stable in that state.
by Sanjana Borle 2K
Sat Oct 12, 2019 2:36 pm
Forum: Properties of Electrons
Topic: Electron After Excited State
Replies: 7
Views: 34

Re: Electron After Excited State

If an electron gets excited, that means that it needs to have absorbed energy in order to jump to another energy level. However, when it jumps to another level its position becomes less stable then it gives off energy in the form of a photon of light and goes back down.
by Sanjana Borle 2K
Sat Oct 05, 2019 4:27 pm
Forum: Balancing Chemical Reactions
Topic: balancing charges
Replies: 4
Views: 55

Re: balancing charges

Since we aren't dealing with oxidation reduction reactions yet it is not needed to balance charges; we are simply balancing the number of atoms of certain elements on each side. Balancing charges will not be covered on Friday's test.
by Sanjana Borle 2K
Sat Oct 05, 2019 4:25 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Wrong Textbook
Replies: 12
Views: 164

Re: Wrong Textbook

I also have the 6th edition and all the problems and writing is identical, as well as the problem numbers. Just be careful not to mix up page numbers as they are different in the 6th and 7th editions.
by Sanjana Borle 2K
Fri Oct 04, 2019 1:29 pm
Forum: Balancing Chemical Reactions
Topic: Fractions in front of compounds
Replies: 12
Views: 93

Re: Fractions in front of compounds

Because it doesn't make much sense to have a fraction of a mole (since a mole is not a perfect number) it should be multiplied until all stoichiometric coefficents are whole numbers.
by Sanjana Borle 2K
Fri Oct 04, 2019 1:27 pm
Forum: Molarity, Solutions, Dilutions
Topic: Volume formulas
Replies: 6
Views: 68

Re: Volume formulas

For me the most straightforward way is to use the equation m1v1=m2v2 then plug in molarities and volumes to find the unknown. I believe this equation (or alternate versions of this) should be all we need for this section.
by Sanjana Borle 2K
Fri Oct 04, 2019 1:26 pm
Forum: Empirical & Molecular Formulas
Topic: When should one start rounding in a problem?
Replies: 11
Views: 113

Re: When should one start rounding in a problem?

You should probably keep from rounding until the very end, then round; I believe that is the most accurate.

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