Search found 32 matches
- Sun Jun 10, 2018 6:04 pm
- Forum: Lewis Structures
- Topic: Central atom and octet rule?
- Replies: 12
- Views: 3082
Re: Central atom and octet rule?
Central atoms can have fewer than 8 atoms or more than 8 atoms depending on the circumstances. If an element has access to d-orbitals (group 3 and beyond), then there can be more than 8 electrons on the central atom.
- Sun Jun 10, 2018 5:57 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal charge
- Replies: 5
- Views: 704
Re: Formal charge
When checking formal charge, bonds count as a single electron if you are not using the equation and just counting, but if you are trying to satisfy an octet, a single bond counts as two electrons for an atom.
- Sun Jun 10, 2018 5:54 pm
- Forum: Properties of Light
- Topic: Wave and Particle
- Replies: 10
- Views: 1252
Re: Wave and Particle
Light has the characteristics of both a wave and a particle. A photon has a wavelength and also contains energy and can dislodge an electron from an atom with enough energy.
- Tue May 29, 2018 5:33 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone pairs on non-central atoms
- Replies: 4
- Views: 806
Re: Lone pairs on non-central atoms
The negative charge of the lone pair electrons result in the repulsion of other electrons in the molecule. The repulsion creates the different bond angles.
- Tue May 29, 2018 5:32 pm
- Forum: Ionic & Covalent Bonds
- Topic: Polar Vs. Non-Polar
- Replies: 7
- Views: 1376
Re: Polar Vs. Non-Polar
Polarity depends on the electronegativity difference. Ranges 0 - 0.4 is non-polar, 0.5 - 1.7 is polar, 1.7 < is ionic.
- Tue May 29, 2018 5:24 pm
- Forum: Resonance Structures
- Topic: Resonance [ENDORSED]
- Replies: 5
- Views: 944
Re: Resonance [ENDORSED]
I'm not entirely sure but I believe the question if asking for the resonance structure with the lowest formal charge.
- Tue May 29, 2018 5:20 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: lone pairs
- Replies: 3
- Views: 434
Re: lone pairs
The negative charge of the lone pair electrons repulse other negatively charged electrons in a molecule. This repulsion results in the various bond angles of a molecule.
- Tue May 29, 2018 5:16 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond angle
- Replies: 9
- Views: 1021
Re: Bond angle
The negative charge of lone pair electrons causes repulsion with other electrons. This results in a greater angle in the shape of a molecule.
- Tue May 29, 2018 5:15 pm
- Forum: Ionic & Covalent Bonds
- Topic: Double/Triple Bonds
- Replies: 8
- Views: 1041
Re: Double/Triple Bonds
Any atom can produce a double or triple bond if it contains enough electrons and if it would reduce the formal charge.
- Sun May 20, 2018 3:33 pm
- Forum: Ionic & Covalent Bonds
- Topic: What do the roman numerals mean?
- Replies: 2
- Views: 3845
Re: What do the roman numerals mean?
Roman numerals are a part of nomenclature for compounds when an ion can have multiple charges. The Roman numeral shows the charge of the ion.
- Sun May 20, 2018 3:30 pm
- Forum: DeBroglie Equation
- Topic: De Broglie Wavelength on the Midterm
- Replies: 4
- Views: 728
Re: De Broglie Wavelength on the Midterm
The information provided was for the deBroglie wavelength. C=(Lambda)(Nu) is also used for things moving at the speed of light.
- Sun May 20, 2018 3:25 pm
- Forum: Lewis Structures
- Topic: Dots vs lines to represent electrons
- Replies: 8
- Views: 1974
Re: Dots vs lines to represent electrons
Lines should only be used for bonds while dots should only be used for lone pairs that are not bonded to another atom.
- Sun May 13, 2018 10:04 pm
- Forum: Lewis Structures
- Topic: Meaning of chemical bond
- Replies: 5
- Views: 644
Re: Meaning of chemical bond
The line in a covalent bond represents a shared atom while a line in an ionic bond represents an atom being borrowed completely.
- Sun May 13, 2018 10:02 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: cations
- Replies: 5
- Views: 713
Re: cations
Since it is a caption there are more protons than electrons meaning the electrons feel the attraction of the positively charged protons more making the cation smaller.
- Sun May 13, 2018 9:57 pm
- Forum: Ionic & Covalent Bonds
- Topic: cation vs anion
- Replies: 14
- Views: 3719
Re: cation vs anion
Cations have positive charges and give an electron while anions are negatively charged and receive an electron.
- Sun May 06, 2018 11:49 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Lewis Structure [ENDORSED]
- Replies: 7
- Views: 965
Re: Lewis Structure [ENDORSED]
I believe that as long as the valence electrons are correct then the order of the pair of lone electrons doesn’t matter.
- Sun May 06, 2018 11:47 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: electron config in the "d" sublevel
- Replies: 5
- Views: 837
Re: electron config in the "d" sublevel
I believe that the d subshell must be completely filled first before it can move onto the next one.
- Tue May 01, 2018 2:50 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Question 2.13
- Replies: 1
- Views: 281
Question 2.13
Is the question asking where the positive lobe, negative lobe, and nodal planes are for the Px-, Py-, and Pz- orbitals? For example, for the Px-orbital the nodal plane is located through the z-plane, the positive lobe is located along the x-axis, and the negative lobe is located along the y-axis.
- Sun Apr 29, 2018 5:47 pm
- Forum: Properties of Light
- Topic: photoelectric effect
- Replies: 4
- Views: 520
Re: photoelectric effect
The Photoelectric Effect showed that light acts as both a wave and a particle. Increasing the intensity of the light did not remove an electron but increasing the lights energy did. This showed that each individual photon needs enough energy to remove an electron and the sheer amount of photons will...
- Sun Apr 29, 2018 5:38 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Electron configuration
- Replies: 8
- Views: 766
Re: Electron configuration
in class we had an example of writing the electron configuration of Calcium and we were able to write it as: [Ar]4s^2... why are we able to use Argon to write the electron configuration? Argon is the noble gas before Calcium. Argon has a full valence shell, so using Argon summarizes the electron co...
- Sun Apr 29, 2018 5:32 pm
- Forum: DeBroglie Equation
- Topic: does everything have a wavelength
- Replies: 10
- Views: 1549
Re: does everything have a wavelength
Everything has a wavelength, but not every wavelength is detectable. The wavelength is so inconsequential that it cannot be detected.
- Sun Apr 29, 2018 5:30 pm
- Forum: Student Social/Study Group
- Topic: Rieber Vista(Or any of the Riebers') Chem 14A Study Group Fall 2017
- Replies: 6
- Views: 1137
Re: Rieber Vista(Or any of the Riebers') Chem 14A Study Group Fall 2017
I'm interested in joining the study group. I'm in Rieber Vista. My email is aay1899@gmail.com
- Sun Apr 22, 2018 5:27 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Which Equation Do We Never Use for Light? [ENDORSED]
- Replies: 3
- Views: 590
Which Equation Do We Never Use for Light? [ENDORSED]
During Friday's lecture about quantum mechanics, Dr. Lavelle said we should never use a certain equation for light. What is the equation and in what instances do we use it?
- Sun Apr 22, 2018 5:20 pm
- Forum: Properties of Light
- Topic: still don't uderrsatnd what a photon is [ENDORSED]
- Replies: 20
- Views: 1452
Re: still don't uderrsatnd what a photon is [ENDORSED]
A photon is a packet of light that does not have mass but it does have energy and momentum. A photon also has both wavelike and particle characteristics.
- Sun Apr 22, 2018 5:17 pm
- Forum: Photoelectric Effect
- Topic: Significance of intensity [ENDORSED]
- Replies: 7
- Views: 776
Re: Significance of intensity [ENDORSED]
The intensity of light is the amount of photons. That is why making a light more intense will not result in an electron being removed from an atom. Each individual photon needs enough energy to remove and electron.
- Sun Apr 15, 2018 7:38 pm
- Forum: SI Units, Unit Conversions
- Topic: Length Units
- Replies: 15
- Views: 1522
Re: Length Units
I would use SI units in the answer unless explicitly asked for a specific unit.
- Sun Apr 15, 2018 7:36 pm
- Forum: Balancing Chemical Reactions
- Topic: Balancing Chemical Equations and Combustion
- Replies: 7
- Views: 1021
Re: Balancing Chemical Equations and Combustion
In a combustion reaction CO2 and H2O will always be a product. From there you will be able to balance the equation like a normal equation.
- Sun Apr 15, 2018 7:27 pm
- Forum: Properties of Light
- Topic: Speed of Light
- Replies: 2
- Views: 185
Re: Speed of Light
The value of the speed of light does change depending on the medium it is going through. For example light travels slower in water than in air. A vacuum is an area with no particles. An example of a vacuum is outer space.
- Sun Apr 15, 2018 7:25 pm
- Forum: Limiting Reactant Calculations
- Topic: actual vs. theoretical yield [ENDORSED]
- Replies: 6
- Views: 1583
Re: actual vs. theoretical yield [ENDORSED]
Theoretical yield is the amount of products the reactants will make under perfect conditions while the actual yield is the amount of products that the reaction produces. The discrepancies are caused by side reactions, reactants sticking to the flask, etc...
- Fri Apr 13, 2018 12:49 pm
- Forum: Properties of Light
- Topic: Speed in vacuum
- Replies: 3
- Views: 797
Re: Speed in vacuum
C is a constant that represents the speed of light in a vacuum. Light will constantly travel at this speed, but this is specifically for a vacuum. The speed of light can change through different mediums. An example of this would be the different speed of light traveling through water.
- Fri Apr 13, 2018 12:47 pm
- Forum: Properties of Light
- Topic: Frequency and wavelength [ENDORSED]
- Replies: 4
- Views: 541
Re: Frequency and wavelength [ENDORSED]
Wavelength and Frequency do have an inverse relationship. The longer a wave is the less frequently it will repeat itself. If a wave repeats more frequently the length of the wave would be shortened.
- Fri Apr 13, 2018 12:44 pm
- Forum: SI Units, Unit Conversions
- Topic: Sig Figs
- Replies: 9
- Views: 1097
Re: Sig Figs
I believe that rounding up is correct as long as it is consistent. If the answer is relatively close I don't think there would be a problem.