Search found 31 matches
- Sat Dec 08, 2018 10:11 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: pH to salt solution
- Replies: 1
- Views: 20
Re: pH to salt solution
Given the molarity and volume of the basic solution, you find the concentration of OH- ions. With that information, you can find the pOH and subtract that from 14, and you will have the pH. Hope this basic skeleton of how to solve it helps. Basically find out how many moles of the molecule there is ...
- Sat Dec 08, 2018 10:02 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: What are salts...
- Replies: 4
- Views: 39
Re: What are salts...
Salts are basically just ionic compounds such as NaCl. They raise or lower pH by ionizing in solution and either creating more hydronium or hydroxide ions. An example of an acidic salt would be NH4Cl. In solution, the NH4 would donate its H proton to H20 creating H30+. more acidic!
- Sat Dec 08, 2018 9:57 pm
- Forum: Sigma & Pi Bonds
- Topic: Churro 17
- Replies: 2
- Views: 37
Re: Churro 17
Yes it is asking for pi and sigma as well as the hydridization. There is an example given of what they are asking for: sigma(C2sp^2, C2sp^2).
- Sat Dec 08, 2018 9:55 pm
- Forum: Bronsted Acids & Bases
- Topic: Strong acid
- Replies: 5
- Views: 28
Re: Strong acid
It is a strong acid because it fully ionizes and dissociates in water. That means there are more hydronium ions in solution making it more acidic.
- Sat Dec 08, 2018 9:51 pm
- Forum: Bronsted Acids & Bases
- Topic: Strong base
- Replies: 5
- Views: 42
Re: Strong base
NaOH is a strong base because it fully dissociates in water. That means there are more OH- ions floating in solution making it more basic.
- Sat Dec 08, 2018 6:29 pm
- Forum: Calculating the pH of Salt Solutions
- Topic: Ph to salt solution
- Replies: 2
- Views: 23
Re: Ph to salt solution
This is what Lyndon did to himself for one of the problems in his review session, but NO it is not needed to know how to do for the final.
- Sat Dec 08, 2018 6:28 pm
- Forum: Naming
- Topic: Common Ligands
- Replies: 2
- Views: 13
Re: Common Ligands
I think it'll be useful to have memorized for when you encounter any problems with naming. Do enough practice problems and the names should be committed to memory.
- Sat Dec 08, 2018 6:25 pm
- Forum: Conjugate Acids & Bases
- Topic: NH3, acid or base?
- Replies: 2
- Views: 36
Re: NH3, acid or base?
I think for almost all the reactions we've worked with, NH3 acts a Bronsted base because it accepts the proton.
- Sat Dec 08, 2018 6:22 pm
- Forum: Dipole Moments
- Topic: Forces Present in molecules
- Replies: 3
- Views: 24
Re: Forces Present in molecules
You can know what type of intermolecular forces a molecule goes through by know its shape and polarity. By knowing that there is a dipole in a molecule, you will know that opposite dipoles of molecules with attract.
- Sat Dec 08, 2018 6:20 pm
- Forum: Electronegativity
- Topic: Exceptions
- Replies: 3
- Views: 27
Re: Exceptions
Not sure if there are any exceptions to this trend, but it might be a good idea to take a quick look at the electronegativity periodic table. You'll be able to see for yourself the electronegativites of each element and be able to see the trends.
- Sat Dec 08, 2018 6:16 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bent
- Replies: 1
- Views: 27
Re: Bent
I believe including the angle would be enough since that would specify which bent shape it is.
- Tue Dec 04, 2018 10:42 pm
- Forum: Naming
- Topic: Knowing oxidation states
- Replies: 11
- Views: 70
Re: Knowing oxidation states
I'm not sure about the textbook, but there's this sheet on Professor Lavelle's website:
https://lavelle.chem.ucla.edu/wp-conten ... pounds.pdf
https://lavelle.chem.ucla.edu/wp-conten ... pounds.pdf
- Tue Dec 04, 2018 10:32 pm
- Forum: Hybridization
- Topic: S character
- Replies: 3
- Views: 59
Re: S character
Oh okay, I was just overthinking it. Thank you!
- Tue Dec 04, 2018 10:28 pm
- Forum: Naming
- Topic: Difference between cis and trans
- Replies: 4
- Views: 36
Re: Difference between cis and trans
If you need help visualizing cis vs trans, take a look at the molecules cis-dichloroethene and trans-dichloroethene!
- Thu Nov 29, 2018 5:57 pm
- Forum: Hybridization
- Topic: S character
- Replies: 3
- Views: 59
S character
In 6th edition textbook, question 4.43, it talks about s-character in regards to hybridization. What is s character?
- Thu Nov 29, 2018 4:44 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: trans/cis
- Replies: 4
- Views: 26
Re: trans/cis
Hello, The way I imagine trans/cis molecules is that there are two different lewis structures that the molecule would be. To differentiate, which lewis structure is correct and what the molecule they are asking for is, trans or cis is added to the front. Cis molecules like cis-dichloroethene are pol...
- Sun Nov 04, 2018 9:33 pm
- Forum: Properties of Electrons
- Topic: Electron Configuration
- Replies: 7
- Views: 59
Re: Electron Configuration
Very interesting, Melissa. I googled this phenomenon, and it says that this is the electron configuration because experiment has shown. Our usual methods don't apply to this Pd because it's an exception due to what has been found in experiment. I doubt this we will need to know this. We'll only need...
- Sun Nov 04, 2018 9:21 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Question from textbook
- Replies: 2
- Views: 42
Re: Question from textbook
First, use the 2.111g Na2CO3 and the 250.0mL and find the molarity. I got .07980mol/L. For part a, take the 2.15mmol Na+ ion and convert into moles. There are two Na+ ion per Na2CO3 molecule, so using dimensional analysis you find out how many moles of Na2CO3 you need. Using the molarity we found, w...
- Sun Nov 04, 2018 8:27 pm
- Forum: Administrative Questions and Class Announcements
- Topic: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]
- Replies: 121
- Views: 4196
Re: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]
Thank you so much, Lyndon. These are going to help me a lot as I'm last minute cramming.
- Sun Oct 28, 2018 9:19 pm
- Forum: Trends in The Periodic Table
- Topic: Atomic Radius
- Replies: 4
- Views: 36
Re: Atomic Radius
What Ana said above is correct. Adding another electron to the outer shell would increase the electron to electron repulsion, thus making the shell and atomic radius increase ever so slightly.
- Sun Oct 28, 2018 9:15 pm
- Forum: Trends in The Periodic Table
- Topic: Lewis Structures
- Replies: 7
- Views: 63
Re: Lewis Structures
I'm not sure if they can just go anywhere. Just make sure the dots/electrons are paired up and the sides surrounding the atom (where there's not a bond).
- Sun Oct 28, 2018 9:01 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Energy Release in Electron Affinity
- Replies: 1
- Views: 42
Re: Energy Release in Electron Affinity
The way I'd rationalize this is knowing that electron affinity, or the energy being released after an electron is added to a neutral atom, is opposite to ionization energy. It takes energy to be put in to break the bonds and release an electron from an atom, so it would only make sense that energy w...
- Sun Oct 28, 2018 8:51 pm
- Forum: Trends in The Periodic Table
- Topic: Question 2.81 (Sixth Edition)
- Replies: 2
- Views: 35
Re: Question 2.81 (Sixth Edition)
I remember learning this somewhat in AP Chemistry. The way that I'd rationalize it is that Nitrogen's orbital is half filled. They are all spinning the same way. Orbitals that are completely filled as well as half filled are relatively stable. Of course the fully filled orbital is more stable than t...
- Sun Oct 21, 2018 11:09 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Molecular Shape
- Replies: 2
- Views: 113
Re: Molecular Shape
We need to know the difference because the topic of electron configuration will be a large topic to be discussed later. We will probably be asked later to figure the different orbitals and shapes of different things.
- Sun Oct 21, 2018 11:07 pm
- Forum: Bond Lengths & Energies
- Topic: Bond length Correlation
- Replies: 2
- Views: 113
Re: Bond length Correlation
I think there is a relationship between the two because for a bond length to be shorter, there needs to be more bonded electrons between the two. The energy is bond will be higher with more bonded electrons because it will take more energy to break the bond since the bond is shorter and stronger.
- Thu Oct 11, 2018 10:45 pm
- Forum: Balancing Chemical Reactions
- Topic: L.5 Part B Sixth Edition [ENDORSED]
- Replies: 5
- Views: 110
L.5 Part B Sixth Edition [ENDORSED]
I can't seem to get the correct answer for part b. I converted 3.500x10^3 kg Al to g and then to moles by dividing by its molar mass. Then I used molar ratios to find out how many moles of Al2O3 is made, turned that to g and then to kg. My answer doesn't seem to match. Am I making any wrong steps?
- Thu Oct 11, 2018 9:43 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: molar masses on the test
- Replies: 7
- Views: 137
Re: molar masses on the test
Even though we'll be given molar masses from the periodic table, it doesn't hurt to memorize some of the more common elements! After doing a whole bunch of practice problems, molar masses of common elements used will just be ingrained in your memory. Oxygen, Carbon, Hydrogen, and Nitrogen are nice o...
- Thu Oct 11, 2018 9:36 pm
- Forum: Properties of Light
- Topic: Black Body Radiation
- Replies: 4
- Views: 34
Re: Black Body Radiation
The previous reply already explained what black body radiation is, but I believe during lecture that Professor Lavelle said that we don't need to worry ourselves with knowing and remembering about what black body radiation does because we will not be tested on it.
- Thu Oct 04, 2018 4:28 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: diatomic molecules
- Replies: 5
- Views: 43
Re: diatomic molecules
Dear friend, There is a beautiful computer website and even smartphone application called Quizlet! You are able to make flashcards for anything and test yourself anywhere at any time as long as you have your mobile device or computer. There are even games and tests that Quizlet can do for you. The b...
- Thu Oct 04, 2018 4:18 pm
- Forum: SI Units, Unit Conversions
- Topic: Homework: E1, 6th Ed.
- Replies: 4
- Views: 69
Re: Homework: E1, 6th Ed.
Dear Michelle Bui, I also had trouble with this question because my answer was always far off from the actual answer. Soon I came to realize my mistake. You start off by multiplying Avogadro's number to the amount of moles of Ag to the get the number of atoms you have in the fiber. Once you have tha...
- Thu Oct 04, 2018 4:10 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Fundamental G, Number 5 6th Edition
- Replies: 1
- Views: 42
Re: Fundamental G, Number 5 6th Edition
Hello dear classmate, Your method of solving the problem would exactly what I would do. The beautiful thing about chemistry is that there are multiple ways about solving a problem. However, there is a mistake in one of your steps which is why your answer is off from the solutions manual. When you mu...