Search found 30 matches

by Sarah Jeong 4F
Thu Dec 06, 2018 7:16 pm
Forum: Naming
Topic: Naming Complexes
Replies: 1
Views: 44

Re: Naming Complexes

You use suffix bis-, tris-, etc. when there already is bi-, tri-, etc. in the ligand. For example, Dichlorobis(ethylenediamine)cobalt(III) chloride.
by Sarah Jeong 4F
Thu Dec 06, 2018 7:09 pm
Forum: Naming
Topic: oxidation number
Replies: 4
Views: 86

Re: oxidation number

You could figure out the charge of the ligands using the periodic table. For example nitrogen would have a -5 charge when it's considered as an ion, while Carbon has a +4 charge. So the ligand CN would have a total -1 charge. For common compounds such as H20, NH3, and CN-, it is better to memorize t...
by Sarah Jeong 4F
Thu Dec 06, 2018 6:56 pm
Forum: Naming
Topic: K3[CoF6]
Replies: 2
Views: 58

K3[CoF6]

Why do we not follow the alphabetic rule when we say that K3[CoF6] is "potassium hexafluorocobaltate(3)" rather than "potassium cobaltate(3)hexafluoro?"
by Sarah Jeong 4F
Sat Dec 01, 2018 2:49 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: repulsion strength
Replies: 3
Views: 134

Re: repulsion strength

Like electrons in a lone pair has a stronger repulsion strength than a shared bond electron, two lone pairs would have a stronger repulsion strength than a shared bond electron+lone pair.
by Sarah Jeong 4F
Sat Dec 01, 2018 2:42 pm
Forum: Naming
Topic: Naming
Replies: 3
Views: 69

Re: Naming

And also, I know Dr. Lavelle wants us to know the lewis structures for the common polyatomic ions such as nitrate, sulfate, carbonate. It is useful to know it at the top of your head for during exams!
by Sarah Jeong 4F
Sat Dec 01, 2018 2:39 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Induced dipoles
Replies: 5
Views: 166

Re: Induced dipoles

Adding on, this phenomenon is also known as Van der Waals Force. This takes place in every single molecular relationship such as hydrogen and dipole-ionic.
by Sarah Jeong 4F
Thu Nov 22, 2018 10:57 am
Forum: Bond Lengths & Energies
Topic: H bonding
Replies: 12
Views: 333

Re: H bonding

You can visually see this as a large pot of water(more hydrogen bonds) takes a higher temperature to boil than a small pot of water.
by Sarah Jeong 4F
Thu Nov 22, 2018 10:52 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Bent - Lone Pairs
Replies: 8
Views: 197

Re: Bent - Lone Pairs

Adding on, if there were two lone pairs, then the angles between the atoms would be smaller than if there were only one lone pair even if they were both bent shape.
by Sarah Jeong 4F
Thu Nov 22, 2018 10:49 am
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Sigma and Pi Bonds
Replies: 3
Views: 78

Re: Sigma and Pi Bonds

Hello Brice,
this picture is pretty helpful.
After every first single bond, it is a pi bond.
So if it was a double bond(which is basically 2 single bonds), then the first single bond would be sigma, and everything after is pi bond.

image.png
image.png (11.34 KiB) Viewed 72 times
by Sarah Jeong 4F
Thu Nov 15, 2018 11:20 am
Forum: SI Units, Unit Conversions
Topic: bond angles
Replies: 5
Views: 276

Re: bond angles

You could think logically for some of them, for example how a triangular planar is equal angles, and therefore is 360/3=120 degrees. For some, it's just pure memorization. This is a very useful chart I found!
image.png
by Sarah Jeong 4F
Thu Nov 15, 2018 11:12 am
Forum: SI Units, Unit Conversions
Topic: lewis structure shape
Replies: 6
Views: 279

Re: lewis structure shape

Each of the shapes are affected by mainly two things: If they have lone pairs and how many different bonds they have with different atoms.
by Sarah Jeong 4F
Thu Nov 15, 2018 10:58 am
Forum: Determining Molecular Shape (VSEPR)
Topic: bond angle
Replies: 4
Views: 89

Re: bond angle

Usually if there is a electronegative difference from different elements, or the presence of lone pairs, does it affect the angle in between.
by Sarah Jeong 4F
Sat Nov 10, 2018 6:24 pm
Forum: Dipole Moments
Topic: Dipole Induced Dipole
Replies: 2
Views: 54

Re: Dipole Induced Dipole

This is the same thing as Van der waals, where it is present in all types of bonds: ionic, covalent, hydrogen.
by Sarah Jeong 4F
Sat Nov 10, 2018 6:22 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Polarizability v. Electronegativity
Replies: 3
Views: 117

Re: Polarizability v. Electronegativity

Basically if a molecule has a great amount of electronegative difference, they are usually polar. For example, H20. The electronegative difference is large, therefore more electrons go toward oxygen, giving the oxygen a partial negative, and hydrogen a partial positive(polar molecule).
by Sarah Jeong 4F
Sat Nov 10, 2018 6:16 pm
Forum: Lewis Structures
Topic: polyatomic ions
Replies: 2
Views: 80

Re: polyatomic ions

Yes, it is basically the same process as a polyatomic lewis structure, except you add/subtract valence electrons(based on the charge given in the chemical formula) on the actual lewis structure. Also bracket it and put the charge on the outside. So for example, on the attached picture, it would regu...
by Sarah Jeong 4F
Thu Nov 01, 2018 11:35 am
Forum: Photoelectric Effect
Topic: Rate at which electrons are emitted
Replies: 2
Views: 169

Re: Rate at which electrons are emitted

Basically if you are over the threshold level, then increasing the intensity(#of electrons), will increase the rate of the electrons that are emitted.
by Sarah Jeong 4F
Thu Nov 01, 2018 11:32 am
Forum: Lewis Structures
Topic: How to determine central atom
Replies: 8
Views: 162

Re: How to determine central atom

Adding on, mostly in Lewis Structures, the element that is used the least like the C in CH4 usually goes in the middle, because it is also based on symmetry.
by Sarah Jeong 4F
Thu Nov 01, 2018 11:30 am
Forum: Trends in The Periodic Table
Topic: Electron Affinity, Ionization energy, and Effective Nuclear Charge
Replies: 2
Views: 54

Re: Electron Affinity, Ionization energy, and Effective Nuclear Charge

Electronic Affinity & Ionization energy are the same concept, where electronic affinity is how strong the element wants the e-, and the ionization energy is how strong energy is needed to remove a e-. Electronic Affinity and Ionization energy are stronger as you go up and to the right, because i...
by Sarah Jeong 4F
Thu Oct 25, 2018 10:20 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Ionization Energy
Replies: 3
Views: 84

Re: Ionization Energy

Adding on, this could be seen in NaCl, where the Na from the s block, and the Cl from the p block is very reactive with each other in order to create more stable bond.
by Sarah Jeong 4F
Thu Oct 25, 2018 10:12 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Nodal Planes on f-orbitals
Replies: 4
Views: 164

Re: Nodal Planes on f-orbitals

F orbitals would have 3 nodal planes. The number of nodal planes is equal to the value of the angular momentum quantum number, l. For example s orbital would have 0 nodal planes, p orbital would have 1 nodal plane, d would have 2 nodal plane, and so on.
by Sarah Jeong 4F
Thu Oct 25, 2018 10:05 pm
Forum: Properties of Light
Topic: Chapter 1 number 33
Replies: 2
Views: 118

Re: Chapter 1 number 33

Adding on, the formula for the photoelectric effect is: Ephoton=Threshold Level+Kinetic Energy of the electron.
by Sarah Jeong 4F
Thu Oct 18, 2018 5:53 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Position v. Momentum
Replies: 1
Views: 54

Re: Position v. Momentum

The way my TA explained it was, imagine if you had a chair(that you can't see, but is somewhere) and you pushed it, then it appears, the position of the chair is now more precise, however because you influenced the position, the less precise the momentum is bc you changed its momentum. So if you ima...
by Sarah Jeong 4F
Thu Oct 18, 2018 5:35 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Emission Spectrum and Atomic Spectrum
Replies: 2
Views: 48

Re: Emission Spectrum and Atomic Spectrum

Hi sonalivij, If you're asking about the photoelectric effect, then it is true that we only see light(from e- emission) that is reflected. But the light that is absorbed is also seen because we are pointing actual photons(lights) into the metal. That is why we see the light that is being absorbed an...
by Sarah Jeong 4F
Thu Oct 18, 2018 5:08 pm
Forum: Properties of Light
Topic: Speed of Light
Replies: 5
Views: 149

Re: Speed of Light

Hi Matia,
I think in terms of sig figs for constant, just copy the full number from that is given on the formula sheet.
But for the actual final answer, use the sig figs of the numbers that are given in the question.
by Sarah Jeong 4F
Thu Oct 11, 2018 11:13 am
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Molar mass
Replies: 3
Views: 179

Re: Molar mass

Hi! If you're asking when we have a grams--> molar mass--> coefficient, then you only multiply by the coefficient if you're changing compound to another compound. Or if you're changing compound to atom. coefficient.jpg In this example, you multiply the given grams by the molar mass to get the moles ...
by Sarah Jeong 4F
Thu Oct 11, 2018 11:00 am
Forum: Photoelectric Effect
Topic: equations
Replies: 1
Views: 71

Re: equations

Hi!
The E=hv, is for the energy of the photon(light) that coming to hit the metal. And Ek=1/2mv^2 is the kinetic energy of the electron that is given out, if the energy of the photon is over the threshold energy.
The kinetic energy=energy of photon-threshold energy.
photoelectric.jpg
by Sarah Jeong 4F
Thu Oct 11, 2018 10:53 am
Forum: Properties of Electrons
Topic: Energy of Photons
Replies: 1
Views: 71

Re: Energy of Photons

Hi!
I would think keV is 10^3eV. And for the eV, I attached a picture.
energy.jpg
by Sarah Jeong 4F
Wed Oct 03, 2018 11:33 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Hydrogen Molar Mass HW E9
Replies: 5
Views: 352

Re: Hydrogen Molar Mass HW E9

Usually when you are calculating in between steps for the answer, it is best to use the whole exact number such as the 1.0079. My TA said that they will never take off points for adding more sig figs than necessary. For example, writing 5 sig figs, than the required 3 sig figs. However, they will ta...
by Sarah Jeong 4F
Wed Oct 03, 2018 11:25 pm
Forum: Balancing Chemical Reactions
Topic: Order of balancing an equation
Replies: 8
Views: 137

Re: Order of balancing an equation

Adding on to what Ramsha said, look at both sides to see if there is an element that is present only once on each side. If there is, start with that element. However, if there isn't, find another.
by Sarah Jeong 4F
Wed Oct 03, 2018 11:19 pm
Forum: SI Units, Unit Conversions
Topic: Unit Notation
Replies: 2
Views: 88

Re: Unit Notation

I am guessing that the textbook uses the -1 exponent, because it might be confused as an 'or' sign on print. But at the end of the day, it is the same thing.

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