Search found 30 matches
- Fri Dec 07, 2018 1:59 pm
- Forum: Ionic & Covalent Bonds
- Topic: Inter and Intramolecular Forces
- Replies: 3
- Views: 565
Re: Inter and Intramolecular Forces
Intramolecular forces are those that bind the atoms within the molecule. Intermolecular forces bind the molecules together.
- Fri Dec 07, 2018 1:58 pm
- Forum: Bronsted Acids & Bases
- Topic: Lewis Acids and Bases and Bronsted?
- Replies: 5
- Views: 636
Re: Lewis Acids and Bases and Bronsted?
Lewis acids are electron acceptors, Lewis bases are electron donors. Bronsted acids are proton donors, Bronsted bases are proton acceptors. For Lewis acids/bases, you can usually tell by looking at the Lewis structure. For Bronsted acids/bases, you can tell by whether they form ions by accepting or ...
- Fri Dec 07, 2018 1:56 pm
- Forum: Lewis Acids & Bases
- Topic: Weak Acids/Bases?
- Replies: 5
- Views: 729
Re: Weak Acids/Bases?
Examples of weak acids - CH3COOH, H3PO4, HF Examples of weak bases - NH3, C5H5N, NH4OH Weak bases are only partially protonated in solution. Most of the examples of strong/weak acids and bases you just have to memorize. However, for weak acids there are a few guidelines to distinguish them, such as ...
- Fri Nov 30, 2018 4:28 pm
- Forum: Electronegativity
- Topic: Exceptions
- Replies: 7
- Views: 1096
Re: Exceptions
There are no major exceptions that we need to be aware of - knowing the general periodic trends should be enough.
- Fri Nov 30, 2018 4:20 pm
- Forum: Dipole Moments
- Topic: Molecular Geometry and polarity
- Replies: 5
- Views: 446
Re: Molecular Geometry and polarity
It depends - if atoms of two different elements are attached to the central one, then it will be polar.
- Fri Nov 30, 2018 4:17 pm
- Forum: Sigma & Pi Bonds
- Topic: Triple bond?
- Replies: 18
- Views: 1766
Re: Triple bond?
A triple bond has 1 sigma and 2 pi bonds.
- Mon Nov 26, 2018 10:08 am
- Forum: Hybridization
- Topic: Hybridization
- Replies: 2
- Views: 274
Re: Hybridization
I think it can go into higher f and g orbitals, but we are not required to know those.
- Mon Nov 26, 2018 10:05 am
- Forum: Ionic & Covalent Bonds
- Topic: Resonance
- Replies: 3
- Views: 435
Re: Resonance
Normally, you just draw the Lewis structure for the molecule and then check if there are multiple possible positions for a double/triple bond, which means that there can be more than one Lewis structure.
- Mon Nov 26, 2018 10:03 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Organic Molecules
- Replies: 4
- Views: 457
Re: Organic Molecules
No, I think you apply the same method to organic molecules.
- Sun Nov 18, 2018 4:53 pm
- Forum: Hybridization
- Topic: Sigma and Pi Bonds [ENDORSED]
- Replies: 12
- Views: 1097
Re: Sigma and Pi Bonds [ENDORSED]
The shapes of sigma bonds are more spherical, whereas pi bonds look like a dumbbell with the lobes on either end of the bond axis.
- Sun Nov 18, 2018 4:46 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration of Rutherfordium
- Replies: 2
- Views: 405
Re: Electron Configuration of Rutherfordium
If you count the electrons in that electron configuration, it adds up to 90, which is the atomic number of Thorium. However, you are right that Thorium is in the 5f block; I don't fully understand that part either.
- Sun Nov 18, 2018 4:42 pm
- Forum: Dipole Moments
- Topic: Identifying whether there is a dipole moment
- Replies: 4
- Views: 495
Re: Identifying whether there is a dipole moment
I think they would just expect us to be able to figure it out based on the periodic trends and our general knowledge of electronegativities.
- Fri Nov 09, 2018 10:57 am
- Forum: Resonance Structures
- Topic: Resonance of Ozone
- Replies: 3
- Views: 398
Re: Resonance of Ozone
You should say it only has one type of bond, because it has equal electron distribution throughout the structure, making all its bond lengths and bond strengths equal.
- Fri Nov 09, 2018 10:56 am
- Forum: Octet Exceptions
- Topic: octet exceptions
- Replies: 4
- Views: 503
Re: octet exceptions
Elements that can have expanded octet include P, S, Cl - elements from Period 3 and beyond. This is because these elements have d-orbitals that can expand to accommodate more electrons.
- Fri Nov 09, 2018 10:53 am
- Forum: Trends in The Periodic Table
- Topic: Bond Lenghts
- Replies: 7
- Views: 924
Re: Bond Lenghts
I think you would have to draw the Lewis structure to figure it out.
- Thu Nov 01, 2018 12:20 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Losing Electrons
- Replies: 2
- Views: 306
Re: Losing Electrons
They would lose electrons from 4p first, because the 4 shell is farther from the nucleus than the 3 shell, and the outermost electrons get removed first.
- Thu Nov 01, 2018 12:18 pm
- Forum: Ionic & Covalent Bonds
- Topic: Finding out the likely ion that forms
- Replies: 2
- Views: 250
Re: Finding out the likely ion that forms
It's difficult to predict the most likely ion that would form, because they can take several different oxidation states. I think just having a general idea of the possible transition metal oxidation states (+1, +2, +3, etc) is enough.
- Thu Nov 01, 2018 12:13 pm
- Forum: Resonance Structures
- Topic: Definition of resonance
- Replies: 7
- Views: 907
Re: Definition of resonance
Resonance is a way of describing the electron distribution in molecules with more than one Lewis structure. The resonance hybrid is just a blending of different Lewis structures, such that the electrons are distributed equally across all the bonds instead of being in single/double bonds.
- Fri Oct 26, 2018 10:18 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Exceptions to Trends
- Replies: 3
- Views: 342
Re: Exceptions to Trends
Half-filled and completely filled d orbitals have lower energy which makes them more stable, hence electrons will tend to rearrange themselves towards this state. In chromium and copper, an electron is excited from the 4s orbital to the 3d orbital in order to make the 3d orbital half filled (in the ...
- Fri Oct 26, 2018 10:13 am
- Forum: DeBroglie Equation
- Topic: Measurable wavelength properties
- Replies: 5
- Views: 584
Re: Measurable wavelength properties
"Measurable wavelike properties" just means wave movement that is noticeable/detectable in a lab. The cutoff point for wavelength detection is 10^-18. In this case, since the object is very big, the wavelength wouldn't be measurable.
- Fri Oct 26, 2018 9:54 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration Help
- Replies: 3
- Views: 503
Re: Electron Configuration Help
Khan Academy is usually a good resource, maybe these would help: https://www.khanacademy.org/science/chemistry/electronic-structure-of-atoms/electron-configurations-jay-sal/v/more-on-orbitals-and-electron-configuration https://www.khanacademy.org/test-prep/mcat/physical-processes/electronic-structur...
- Fri Oct 19, 2018 11:20 am
- Forum: Properties of Electrons
- Topic: Rydberg Formula 1.13
- Replies: 3
- Views: 407
Re: Rydberg Formula 1.13
For this equation, the Rydberg constant is 3.29 x 10^15 Hz.
- Fri Oct 19, 2018 11:18 am
- Forum: Properties of Light
- Topic: Do I have to memorize the spectrum?
- Replies: 20
- Views: 1728
Re: Do I have to memorize the spectrum?
You should probably know the visible light range, and which radiations have the highest and lowest frequencies/energies/wavelengths.
- Fri Oct 19, 2018 11:08 am
- Forum: *Shrodinger Equation
- Topic: Orbitals, Lobes, e- density
- Replies: 3
- Views: 636
Re: Orbitals, Lobes, e- density
The wave function is a mathematical representation of the wave motion of the electron, which describes the position and state of the electron. Squaring the wave function gives you the probability of finding an electron in a given region. Orbital and wave function mean the same thing, they can be use...
- Wed Oct 10, 2018 7:06 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Bohr Relation to H-Atom
- Replies: 1
- Views: 76
Re: Bohr Relation to H-Atom
This particular formula was developed based on experimental data for the Hydrogen atom. I believe a more complex equation is needed for multi-electron atoms because of the variation caused by electron-electron repulsion.
- Wed Oct 10, 2018 7:00 pm
- Forum: Einstein Equation
- Topic: Work Function
- Replies: 4
- Views: 337
Re: Work Function
The work function represents the threshold energy, or the minimum energy required to remove an electron from a metal.
- Wed Oct 10, 2018 6:53 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Distinguishing the Balmer and Lyman Series
- Replies: 1
- Views: 291
Re: Distinguishing the Balmer and Lyman Series
The Lyman series consists of the emission lines in the hydrogen spectrum that occur when electrons move to the lowest energy level (n = 1). These wavelengths are all in the UV region. Similarly, the Balmer series represents electrons moving to the second energy level (n = 2). These wavelengths are i...
- Thu Oct 04, 2018 5:14 pm
- Forum: Empirical & Molecular Formulas
- Topic: Question F9
- Replies: 5
- Views: 500
Re: Question F9
I believe you should answer in the form of a ratio.
- Thu Oct 04, 2018 2:28 pm
- Forum: SI Units, Unit Conversions
- Topic: pm to m
- Replies: 6
- Views: 947
Re: pm to m
I think so, given that it was taught in lecture. It would probably be more convenient to memorize the conversions anyway, because it would make calculations much faster.
- Thu Oct 04, 2018 2:26 pm
- Forum: Balancing Chemical Reactions
- Topic: H3, coefficients
- Replies: 7
- Views: 678
Re: H3, coefficients
I think you should be fine, because the equation is balanced, and it does make more sense to write the coefficients as the lowest whole numbers.