Search found 29 matches
- Mon Jun 04, 2018 7:23 pm
- Forum: Octet Exceptions
- Topic: expanded octet
- Replies: 12
- Views: 2713
Re: expanded octet
We know that only the elements that are in Group 3 or below can form an expanded octet, as they have unfilled d-orbitals, which Groups 1 and 2 do not have. This is absolutely correct. keep in mind that these elements dont necessarily always have an expanded octet and are completely happy with 8 ele...
- Mon Jun 04, 2018 7:22 pm
- Forum: Bond Lengths & Energies
- Topic: Energies
- Replies: 4
- Views: 637
Re: Energies
bond length most greatly affects its strength, double and triple bonds are shorter and therefore stronger than a single bond but when comparing two single bonds it is important to look at electronegativity a greater difference in electro negativity between atoms suggests a stronger bond.
- Mon Jun 04, 2018 7:19 pm
- Forum: Lewis Structures
- Topic: 2 lone pairs
- Replies: 5
- Views: 586
Re: 2 lone pairs
lone pairs should be placed as far apart from each other as possible since they have a very strong repulsion this would mean they should be placed on opposite sides (top and bottom)
- Mon Jun 04, 2018 7:16 pm
- Forum: Ionic & Covalent Bonds
- Topic: Polarizability
- Replies: 7
- Views: 904
Re: Polarizability
A polarizable atom/ion is one that has an electron cloud that readily undergoes large distortions meaning the shape of the cloud is changed and influenced by other atoms pull. Larger atoms are more polarizable because the nucleus does not have as strong of an attraction on the farther electrons and ...
- Mon Jun 04, 2018 7:11 pm
- Forum: Dipole Moments
- Topic: determining dipole moment
- Replies: 3
- Views: 622
determining dipole moment
What is the easiest way to identify dipole interactions to be able to determine the polarity of a molecule?
- Mon Jun 04, 2018 7:08 pm
- Forum: Hybridization
- Topic: strength of sigma and pi bonds
- Replies: 10
- Views: 1304
Re: strength of sigma and pi bonds
sigma bonds are able to rotate on their axis and are a stronger where as pi bonds would break if they were rotated
- Mon Jun 04, 2018 7:02 pm
- Forum: Hybridization
- Topic: Sigma and Pi Bonds
- Replies: 5
- Views: 571
Re: Sigma and Pi Bonds
Jonghwee Park 1K wrote:Why are sigma and pi bonds distinguished? More specifically, what makes something a sigma bond and what makes something a pi bond?
sigma and pi bonds differ in shape and the distribution of electron density.
for more see page 121 of the textbook
- Mon Jun 04, 2018 6:55 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angle [ENDORSED]
- Replies: 4
- Views: 776
Bond Angle [ENDORSED]
How do you determine the exact bond angle? I understand that based of lone pairs we can determine whether or not an angle will be less than 109.5 but is there a way to know the exact angle/ make a close estimate or do you have to look up the number.
- Sun May 20, 2018 10:01 pm
- Forum: Bond Lengths & Energies
- Topic: Bond strength of molecules [ENDORSED]
- Replies: 1
- Views: 2132
Bond strength of molecules [ENDORSED]
When given two molecules that each have varying numbers of both single and double bonds how do you find out which molecule has greater bond lengths?
- Sun May 20, 2018 9:55 pm
- Forum: Significant Figures
- Topic: Sig Figs
- Replies: 3
- Views: 565
Sig Figs
I was marked down on the midterm for using incorrect number of significant figures and I was hoping someone could give me a quick overview of the rules so it doesnt happen again. Thanks!
- Sun May 20, 2018 9:44 pm
- Forum: Resonance Structures
- Topic: Stability
- Replies: 3
- Views: 456
Stability
Whats the easiest way to determine the most stable resonance structure?
- Sun May 20, 2018 9:41 pm
- Forum: Resonance Structures
- Topic: Radicals
- Replies: 13
- Views: 1502
Re: Radicals
Free radicals are highly reactive molecules with an unpaired electron, they attack stable molecules in an attempt to "steal" an electron and are neutralized by antioxidants which donate an electron
- Sun May 20, 2018 9:35 pm
- Forum: Dipole Moments
- Topic: Dipole causes
- Replies: 2
- Views: 346
Dipole causes
What causes a dipole moment?
- Sun May 20, 2018 9:28 pm
- Forum: Electronegativity
- Topic: Trends in periodic table
- Replies: 6
- Views: 1274
Re: Trends in periodic table
Trends don't apply to noble gasses and therefore F is the most electronegative atoms
- Sun May 20, 2018 9:26 pm
- Forum: Electronegativity
- Topic: Electronegativity of atoms
- Replies: 3
- Views: 579
Re: Electronegativity of atoms
Group number does not directly correlate to electronegativity, electronegativity is calculated using other methods however a general trend can be seen where atoms become more electronegative as you travel across a period and become less electronegative as you travel down a group
- Sun May 20, 2018 9:20 pm
- Forum: Electronegativity
- Topic: Isoelectronic atoms and their relative electronegativities
- Replies: 2
- Views: 632
Isoelectronic atoms and their relative electronegativities
Since isoelectronic atoms have the same electronic configuration and valence electron number but different atomic radii do they have the same of different electronegativities?
- Sun May 20, 2018 9:17 pm
- Forum: Octet Exceptions
- Topic: Expanded Octet Rules
- Replies: 7
- Views: 1104
Re: Expanded Octet Rules
For the third row of the periodic table, we don't put any d-orbital electrons in their ground state configurations as they don't have any in the d orbital. However, since their energy level is 3 (n=3), they are able to have more electrons. They have a whole new shell rather than be just n=2, so the...
- Sun Apr 29, 2018 5:34 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: # of electrons for a given orbital (homework 2.25)
- Replies: 3
- Views: 479
Re: # of electrons for a given orbital (homework 2.25)
Only 2 electrons can occupy a single orbital, one electron will be spinning up while the other spins down.
- Sun Apr 29, 2018 5:33 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electrons in an Orbital [ENDORSED]
- Replies: 8
- Views: 858
Re: Electrons in an Orbital [ENDORSED]
The fourth quantum number tells us the spin of the electron, it is called the spin magnetic quantum number. This correlates to the fact that two electrons in the same orbital cannot have the same spin.
- Sun Apr 29, 2018 5:29 pm
- Forum: DeBroglie Equation
- Topic: does everything have a wavelength
- Replies: 10
- Views: 1542
Re: does everything have a wavelength
Everything does have a wavelength that can be calculated using the DeBroglie equation. However large objects have such small wavelengths that they cannot be observed or detected (If a wavelength is smaller than 10^-18 it is considered undetectable)
- Mon Apr 23, 2018 11:38 am
- Forum: Photoelectric Effect
- Topic: Application of different formulas [ENDORSED]
- Replies: 4
- Views: 513
Re: Application of different formulas [ENDORSED]
Honestly as long as you know E=hv and v=c/λ you can manipulate them to get most of the formulas you need to solve the problems
- Mon Apr 23, 2018 11:27 am
- Forum: Photoelectric Effect
- Topic: What is work function? [ENDORSED]
- Replies: 15
- Views: 5723
Re: What is work function? [ENDORSED]
The work function is the amount of energy required to expel a single electron from the metal
- Mon Apr 23, 2018 11:26 am
- Forum: Properties of Light
- Topic: Memorizing formulas test 2
- Replies: 16
- Views: 1757
Re: Memorizing formulas test 2
I would recommend doing all the assigned hw problems as opposed to doing only 7, this way after all the repetition you should have formulas memorized and know how to better approach all problems. All formulas and constants should be given though.
- Sun Apr 15, 2018 4:40 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric Effect Expirement [ENDORSED]
- Replies: 4
- Views: 487
Re: Photoelectric Effect Expirement [ENDORSED]
The experiment was key in discovering the one to one interaction between one photon and one electron. The experiment showed that electrons will only be expelled from the metal if the energy of each individual photon is high enough to remove an individual electron. More photons does not necessarily m...
- Sun Apr 15, 2018 4:35 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: When to use MiVi=MfVf
- Replies: 8
- Views: 4439
Re: When to use MiVi=MfVf
Are there some cases where you'll have to use both the M=n/v and MiVi=MfVf equations in a problem? This wouldn't be likely to happen because the first equation is used to find molarity when given the moles and volume of a solution. If you know the moles of the solution then you wouldn't need to use...
- Fri Apr 13, 2018 10:53 am
- Forum: Limiting Reactant Calculations
- Topic: Different ways of determining limiting reactants
- Replies: 2
- Views: 309
Re: Different ways of determining limiting reactants
Honestly you can do whatever works best for you. Personally I calculate the mass of the product for both reactants and compare which one is larger because typically after finding the limiting reactant you are asked to find the theoretical yield and this way you have already done that calculation. So...
- Thu Apr 12, 2018 9:20 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Mass percentage
- Replies: 8
- Views: 1035
Re: Mass percentage
It should always add to 100% but I remember Dr. Lavelle stating that it is a combustion reaction and the mass percentages given do not add up to 100 then it is likely the oxygen that is being left out and will make up the difference.
- Thu Apr 12, 2018 9:17 pm
- Forum: SI Units, Unit Conversions
- Topic: writing out conversions in one long line vs. steps
- Replies: 16
- Views: 1466
Re: writing out conversions in one long line vs. steps
I would recommend writing it out in a chain that way it is easy to see what units are being cancelled out. This is also easy because it allows you to start with the given and work until you reach the desired units and you know you have come to your answer.
- Thu Apr 12, 2018 9:13 pm
- Forum: Empirical & Molecular Formulas
- Topic: Order of elements in molecule
- Replies: 1
- Views: 259
Order of elements in molecule
I was wondering how to determine the order of elements in a molecule when given its components?