Search found 23 matches
- Fri Dec 07, 2018 3:54 am
- Forum: Amphoteric Compounds
- Topic: Polydentate
- Replies: 2
- Views: 251
Re: Polydentate
What is a polydentate would it be just an anion that has more than 4 bonding sites? Can someone give an explanation and example? The textbook (6th edition) defines polydentate as "many-toothed", or able to attach at more than one bonding site simultaneously. Basically, this just means tha...
- Fri Dec 07, 2018 3:39 am
- Forum: Lewis Acids & Bases
- Topic: Determining which H^+ ions are given off
- Replies: 4
- Views: 339
Re: Determining which H^+ ions are given off
It depends on the molecule in question. If it's simple, like HNO3, you can be relatively sure of where the H^+ will come from. If the molecule is more complex, like CH3COOH, it might be necessary to draw a Lewis structure to see which hydrogen is farthest from the central atom; honestly though, it s...
- Fri Dec 07, 2018 3:33 am
- Forum: Bronsted Acids & Bases
- Topic: How to tell if it is an acid or base?
- Replies: 4
- Views: 16874
Re: How to tell if it is an acid or base?
A general rule of thumb is to see whether the molecule predominantly contains (H^+) or (OH^-). Hope this helps!
- Thu Nov 29, 2018 2:02 pm
- Forum: Biological Examples
- Topic: acids
- Replies: 5
- Views: 426
Re: acids
Another reason that our digestive system can handle such liquids is due to its protective coating of mucus. That is the reason that our stomach can handle containing acid and the cause of stomach ulcers (the mucus in a spot decreases, allowing the acid to partially corrode the stomach lining).
- Thu Nov 29, 2018 1:58 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination Number
- Replies: 10
- Views: 965
Re: Coordination Number
The coordination number is the number of ligands bonded to the central atoms. It seems that the coordination number can be found by just tallying the number of other atoms or other, smaller molecules within the complex's formula ( ex. coordination number 4 for [CoCl4]^(2-) or 2 for [HgCl2] ). Usual ...
- Thu Nov 29, 2018 1:42 pm
- Forum: Naming
- Topic: Common Ligand Names
- Replies: 4
- Views: 531
Re: Common Ligand Names
His outline for this unit says that we have to be familiar with the rules for naming, but it doesn't say that we have to we know the actual names.
- Fri Nov 09, 2018 2:53 am
- Forum: Electronegativity
- Topic: electronegativity trends
- Replies: 6
- Views: 652
Re: electronegativity trends
I think it's not so much that there is a causal relationship between electronegativity and electron shielding as a correlative relationship for these periodic trends.
- Fri Nov 09, 2018 2:51 am
- Forum: Resonance Structures
- Topic: homework question 3.71 (6th edition)
- Replies: 3
- Views: 439
Re: homework question 3.71 (6th edition)
To build on what the others have said, you basically need to search for the molecule whose individual formal charges average closest to zero; that molecule is going to be most likely to make the more dominant contribution.
- Fri Nov 09, 2018 2:47 am
- Forum: Ionic & Covalent Bonds
- Topic: Polarizability
- Replies: 9
- Views: 909
Re: Polarizability
Polarizability depends on the number of electrons present and on the size of the pertinent atom. Higher polarizability means that the atom or ion has a more readily distortable electron cloud; the process of distortion itself is known as polarization.
- Mon Nov 05, 2018 3:31 am
- Forum: Administrative Questions and Class Announcements
- Topic: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]
- Replies: 121
- Views: 20040
Re: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]
Can someone explain 1. to me? Thanks in advance! Step 1: Find the molar masses of CO2 and H2O Step 2: Calculate the moles of CO2 and H2O by dividing grams by moles Step 3: Find simplest ratio of two compounds' moles Step 4: Balance full chemical equation ( _ C?H?O? + _ O2 -> _ CO2 + _ H2O ) using a...
- Thu Nov 01, 2018 11:53 pm
- Forum: Coordinate Covalent Bonds
- Topic: Coordinate Covalent Bond Definition
- Replies: 14
- Views: 1873
Re: Coordinate Covalent Bond Definition
For all you 6th edition people out there who see this, the definition is on page 231, stated as "[a] bond in which both electrons come from one of the atoms".
- Thu Nov 01, 2018 11:49 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge
- Replies: 8
- Views: 759
Re: Formal Charge
Heidi Ibarra Castillo 1D wrote:How do you determine your V, L , and S?
Rules for determining FC from the notes from class:
1. Determine number of valence e- for each bound atom
2. Determine number of bonding electrons (S)
3. Determine number of lone e- pairs (L)
4. Determine number of valence e- for each free atom (V)
- Thu Nov 01, 2018 11:42 pm
- Forum: Lewis Acids & Bases
- Topic: Lewis Acids and Bases on Midterm
- Replies: 4
- Views: 527
Re: Lewis Acids and Bases on Midterm
I am in Lecture 3 and Dr. Lavelle said in class that everything up to Wednesday (yesterday) would be covered, which includes Lewis acids and bases. I doubt he really wants us to know a vast amount about them, though; it's probably ok to just know the fact that group 13 elements need 5 electrons to c...
- Sat Oct 20, 2018 1:09 am
- Forum: Ionic & Covalent Bonds
- Topic: Electron Configuration of Cations
- Replies: 8
- Views: 892
Re: Electron Configuration of Cations
Basically, the Roman numeral signifies the number of non-negated positive charges. Hence, copper (I) has a charge of +1 and copper (2) +2.
- Sat Oct 20, 2018 12:58 am
- Forum: Ionic & Covalent Bonds
- Topic: Electron Configuratin
- Replies: 5
- Views: 435
Re: Electron Configuratin
Just think of it like you can only start from the rightmost electrons on. This was actually touched upon in class: the inner sub-shells of electrons actually block the effects of the positively charged nucleus on outer sub-shells.
- Sat Oct 20, 2018 12:56 am
- Forum: Lewis Structures
- Topic: Central atom and octet rule?
- Replies: 12
- Views: 3082
Re: Central atom and octet rule?
is there a rule to know when some atoms are okay with having less than 8 electrons? or should we just memorize some of them and hope for the best? i think it is just memorization but its basically just group 13 and H, He, Li, Be This actually showed up in another post I think, and don't quote me on...
- Fri Oct 12, 2018 7:10 am
- Forum: Quantum Numbers and The H-Atom
- Topic: Balmer/Lyman... Series
- Replies: 4
- Views: 357
Re: Balmer/Lyman... Series
Just to add on a bit to the other answer, the textbook has practice questions that use more than just the Lyman and Balmer levels in terms of both names and level number; it would probably be for the best to memorize them.
- Fri Oct 12, 2018 7:06 am
- Forum: Photoelectric Effect
- Topic: How do I find the mass of an ejected electron?
- Replies: 3
- Views: 462
Re: How do I find the mass of an ejected electron?
As the other posters said, electrons do not change their mass. For this class, you can just use 9.10938E-31 kg as your mass; any more accuracy would probably be overkill for our level of academia.
- Fri Oct 12, 2018 7:03 am
- Forum: Properties of Electrons
- Topic: Electron Energy Levels
- Replies: 2
- Views: 296
Re: Electron Energy Levels
Why are electron energy levels quantized? Why can't electrons exist in between quantized electron energy levels? In response to your question, quantization just means that the electrons can only take integer values of discrete energy packets. Essentially, electrons separate into whole-number levels...
- Thu Oct 04, 2018 10:53 pm
- Forum: Limiting Reactant Calculations
- Topic: What is the mass of AgCl produced?
- Replies: 10
- Views: 9097
Re: What is the mass of AgCl produced?
After guessing a checking i found that the answer is 1.72 g AgCl. I found that the limiting reactant is C6H9Cl3 and that the moles of this compound is .004 moles. To get the answer 1.72, i saw that you have to triple .004 moles and then multiple that by the molar mass which is 143.32 g/mol. I am un...
- Wed Oct 03, 2018 8:59 pm
- Forum: SI Units, Unit Conversions
- Topic: Homework Questions [ENDORSED]
- Replies: 14
- Views: 1264
Re: Homework Questions [ENDORSED]
I'm not completely sure, but the is how I see it: Basically, you're supposed to do problems for whatever the material covered in the week in question is/was. So if you cover information that would be part of multiple letter sections, then you're supposed to do problems from those sections.
- Wed Oct 03, 2018 8:57 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Mole Definition
- Replies: 5
- Views: 739
Re: Mole Definition
A mole is just like a dozen, but instead of signifying 12 of something, it signifies 6.022x10^23. The reason that this number is used is because 6.022x10^23 amu is equal to 1 gram. This helps make calculations simpler. Well, to add on to what this poster is saying, an AMU is a mass unit equal to 1/...
- Wed Oct 03, 2018 8:37 pm
- Forum: SI Units, Unit Conversions
- Topic: Converting between Temperatures (K,C,F)
- Replies: 4
- Views: 439
Re: Converting between Temperatures (K,C,F)
In response to the OP, there is essentially no way to go straight from Fahrenheit to Kelvin or vice versa without including the steps for Celsius.