Search found 31 matches
- Sat Jun 09, 2018 6:52 pm
- Forum: Bronsted Acids & Bases
- Topic: Acid-Base Reactions and Ionic Equations
- Replies: 2
- Views: 1222
Re: Acid-Base Reactions and Ionic Equations
Okay so, for the overall equation, you write the products of the reactants. In this case, an acid and a base produce a salt and water. Once you have formed water, the remaining elements form the salt. In this case, the salt would be NaF. For the ionic equation, you dissociate the strong acid or the ...
- Sat Jun 09, 2018 6:45 pm
- Forum: Bronsted Acids & Bases
- Topic: J.7
- Replies: 2
- Views: 420
Re: J.7
OH- is an anion, and Zn is a cation, since it's Zn2+, and so it would go with OH-.
- Sat Jun 09, 2018 6:44 pm
- Forum: Bronsted Acids & Bases
- Topic: J.1
- Replies: 2
- Views: 443
Re: J.1
H2SO3 is one of the strong acids that we need to know. It's a strong acid because it is polyprotic, and dissociates completely. NH3 is a weak base that we also just need to know.
- Sat Jun 02, 2018 3:03 pm
- Forum: Dipole Moments
- Topic: HW 6.1
- Replies: 3
- Views: 439
Re: HW 6.1
I think it's because the Br atoms are all bonded in an equal manner to the C in the center, and so there isn't really temporary dipole moments.
- Sat Jun 02, 2018 3:02 pm
- Forum: Sigma & Pi Bonds
- Topic: Detail of Bonds
- Replies: 3
- Views: 593
Detail of Bonds
What do we need to know about sigma and pi bonds exactly? I'm not really sure the amount of detail necessary to know.
- Sat Jun 02, 2018 3:00 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR
- Replies: 2
- Views: 325
VSEPR
I'm a little confused as how to determine where I place the lone pairs? Are there specific rules for doing so?
- Sun May 27, 2018 8:26 pm
- Forum: Octet Exceptions
- Topic: Radicals
- Replies: 2
- Views: 417
Re: Radicals
The radical would probably go on the least electronegative, as the other atom, the more electronegative one, attracts more electron pairs.
- Sun May 27, 2018 8:25 pm
- Forum: Octet Exceptions
- Topic: expanded octets
- Replies: 5
- Views: 721
Re: expanded octets
Yes, with an expanded octet, it is referring to the octet of the central atom!
- Sun May 27, 2018 8:23 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Contribution in Formal Charge
- Replies: 2
- Views: 522
Re: Contribution in Formal Charge
It's basically the most stable structure, the one with the lowest energy.
- Fri May 18, 2018 1:18 pm
- Forum: Lewis Structures
- Topic: 3.41c
- Replies: 2
- Views: 353
Re: 3.41c
The way this is written actually tells you how to draw it out! Typically, the chemical formula wouldn't have the carbons written out separately unless it was expressing how to draw it out. Basically, follow the chemical formula from left to right. H2C(NH2)COOH The first section is H2C, which is basi...
- Fri May 18, 2018 1:12 pm
- Forum: Resonance Structures
- Topic: Resonance Structures [ENDORSED]
- Replies: 4
- Views: 563
Re: Resonance Structures [ENDORSED]
I would believe it's through trial and error. But usually, the quickest way to do it in my opinion is to see what is different. For example, if you're drawing a lewis structure for something bonded to 4 oxygens, with 1 single bond and 3 double bonds to oxygen), and so the resonance structures would ...
- Fri May 18, 2018 1:07 pm
- Forum: Lewis Structures
- Topic: Exceptions to the Octet
- Replies: 5
- Views: 605
Exceptions to the Octet
The 3rd row elements and below can expand their octet, but I was wondering if there was a limit to how many extra electrons we can add to these elements?
- Sat May 12, 2018 10:25 pm
- Forum: DeBroglie Equation
- Topic: Bohr vs Speed of Light Equation
- Replies: 3
- Views: 1219
Re: Bohr vs Speed of Light Equation
Typically, looking at the values you already have really helps. For example, if all you have is the wavelength, and the question mentions light, you would use the speed of light equation. If the question asks for frequency, and instead gives you the energy, then you can use the Bohr frequency equati...
- Sat May 12, 2018 10:21 pm
- Forum: Photoelectric Effect
- Topic: light problem
- Replies: 2
- Views: 571
Re: light problem
In general, conversions can be kind of tricky, and so I have this method of using dimensional analysis in order to guarantee I do the conversion correctly. Let's say I'm trying to convert from meters to nanometers, and I have 4.3 \times 10^{-7} meters. I know that 1 nanometer is 10^-9. So, I can set...
- Sat May 12, 2018 10:14 pm
- Forum: Properties of Electrons
- Topic: Electron Affinity
- Replies: 4
- Views: 739
Re: Electron Affinity
The trend for electron affinity is that it increases across a period and decreases down a group, so when answering questions phrased like that, you could just use the trend! Also, electron affinity is how many energy is spent or released when a neutral atom gets an electron added to it.
- Sun May 06, 2018 4:11 pm
- Forum: *Black Body Radiation
- Topic: Midterm?
- Replies: 3
- Views: 843
Re: Midterm?
You don't need to know this for the midterm
- Sun May 06, 2018 4:10 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration Orders?
- Replies: 2
- Views: 477
Re: Electron Configuration Orders?
To double check your answer, make sure that your configuration is written in the order of the n - value, so all the sub-shells associated with 3 are put before any of the sub-shells associated with 4, for example.
- Sun May 06, 2018 4:08 pm
- Forum: Properties of Light
- Topic: The visible spectrum
- Replies: 4
- Views: 708
Re: The visible spectrum
The line spectrum shows the specific wavelengths that are being absorbed/emitted, whereas the continuous spectrum shows a continuum of wavelengths. A line spectrum is discrete, while the continuous spectrum isn't.
- Sat Apr 28, 2018 4:08 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: What do l and m represent? [ENDORSED]
- Replies: 6
- Views: 1033
What do l and m represent? [ENDORSED]
I'm just a little confused as to what the letters l and m represent? I know that n is the energy level, but what are l and m? Thank you.
- Sat Apr 28, 2018 4:05 pm
- Forum: Properties of Light
- Topic: Energy difference in excited electrons
- Replies: 3
- Views: 350
Re: Energy difference in excited electrons
When the two n values aren't given, one will be usually given in a hidden way. The question might mention the series that's used or the part of the spectrum. For example, the question might say the Lyman series (and then you would know that the value of n we are reaching is n=1), or that it's in the...
- Sat Apr 28, 2018 4:02 pm
- Forum: DeBroglie Equation
- Topic: Conversion [ENDORSED]
- Replies: 2
- Views: 379
Re: Conversion [ENDORSED]
Glad you figured out your mistake! For the future though, I like to use dimensional analysis for my conversions as to avoid any mistakes or confusion. I use the following set up. Let's say I'm trying to convert from meters to nanometers, and I have 4.7\times 10^{-7} meters. I know that 1 nanometer i...
- Sun Apr 22, 2018 11:12 pm
- Forum: Properties of Light
- Topic: Homework 1.5
- Replies: 6
- Views: 603
Re: Homework 1.5
Keep in mind that the relationship between frequency, energy, and wavelength is as follows:
The longer the wavelength the lower the frequency and that means less energy.
The longer the wavelength the lower the frequency and that means less energy.
- Sun Apr 22, 2018 11:10 pm
- Forum: DeBroglie Equation
- Topic: Quanta
- Replies: 5
- Views: 705
Quanta
Can someone explain what quantum really means? Like how do "quanta" related to what we're learning?
- Sun Apr 22, 2018 11:09 pm
- Forum: Einstein Equation
- Topic: Joules unit conversion [ENDORSED]
- Replies: 2
- Views: 339
Joules unit conversion [ENDORSED]
I was just wondering what the unit conversion was for Joules? Something with kg and m and s?
- Sun Apr 15, 2018 2:40 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Electron Energy Levels
- Replies: 3
- Views: 367
Re: Electron Energy Levels
The energy levels decrease because the electrons are further away from the nucleus, where the protons are. That means that less energy is needed to remove electrons because the attraction between the protons and electrons is weaker due to increased distance.
- Sun Apr 15, 2018 2:34 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Homework 3
- Replies: 3
- Views: 281
Homework 3
Does anyone know what this week's homework should be for? Like from which outline do we pick homework questions? Thanks!
- Wed Apr 11, 2018 2:16 pm
- Forum: SI Units, Unit Conversions
- Topic: Avagrado's Number [ENDORSED]
- Replies: 6
- Views: 1092
Re: Avagrado's Number [ENDORSED]
It's usually for the number of molecules or atoms, depending on the question, but if you have something that asks for the number of molecules AND then the number of atoms, you can do the following. You would first use Avogadro's constant for the number of molecules, then you multiply that by the li...
- Sun Apr 08, 2018 9:26 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Accuracy vs Precision
- Replies: 23
- Views: 2597
Re: Accuracy vs Precision
Precision is how close to each other they are, and accuracy is how close to the true value they are.
- Sun Apr 08, 2018 9:24 pm
- Forum: SI Units, Unit Conversions
- Topic: Avagrado's Number [ENDORSED]
- Replies: 6
- Views: 1092
Re: Avagrado's Number [ENDORSED]
It's usually for the number of molecules or atoms, depending on the question, but if you have something that asks for the number of molecules AND then the number of atoms, you can do the following. You would first use Avogadro's constant for the number of molecules, then you multiply that by the lit...
- Sun Apr 08, 2018 9:09 pm
- Forum: SI Units, Unit Conversions
- Topic: Sig figures
- Replies: 9
- Views: 570
Re: Sig figures
If you're adding, you use the number with the least number of decimal places as your determinant for the number of decimal places for your answer. Meanwhile, if you're multiplying, the one with the least number of SF should be used to determine the number of SF for the answer.
- Sun Apr 08, 2018 9:08 pm
- Forum: SI Units, Unit Conversions
- Topic: Sig figures
- Replies: 9
- Views: 570
Re: Sig figures
If you're adding, you use the number with the least number of decimal places as your determinant for the number of decimal places for your answer. Meanwhile, if you're multiplying, the one with the least number of SF should be used to determine the number of SF for the answer.