Search found 32 matches
- Mon Jun 04, 2018 3:30 pm
- Forum: Bond Lengths & Energies
- Topic: Ionic Character
- Replies: 12
- Views: 15581
Re: Ionic Character
The smaller the atomic ration and the greater electronegativity mean a greater ionic character. Since the trends for these increase as you go right and up on the periodic table you will find the elements with greater ionic character there. The person above is actually wrong because NaBr has greater ...
- Mon Jun 04, 2018 3:11 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: 4 ligands shape?
- Replies: 6
- Views: 758
Re: 4 ligands shape?
I suggest you first figure out the Lewis structure then see if the 4 include any lone pairs, if there is a lone pair it is a square planar and so the angles are different, becuse the lone pairs decrease it through repulsion.
- Mon Jun 04, 2018 3:05 pm
- Forum: Hybridization
- Topic: Meaning of hybridization
- Replies: 2
- Views: 436
Re: Meaning of hybridization
From what I know, the point is just to redistribute the electrons even if the amount remains the same. We redistribute them to make them suitable for chemical bonds through factors like energy and shape. Hope that helps
- Wed May 30, 2018 9:34 pm
- Forum: Resonance Structures
- Topic: Resonance Review
- Replies: 3
- Views: 640
Resonance Review
I know this topic is from a while ago, but after the test we just got back, I am confused as to what resonance is now. I thought it was just like a variation to the structure given. I am not sure what are the rules or how to properly give a resonance structure. Anything would help, or going over the...
- Wed May 30, 2018 9:30 pm
- Forum: Lewis Structures
- Topic: Electrons in Valence Shell
- Replies: 4
- Views: 838
Re: Electrons in Valence Shell
You can also use the principle quantum numbers of the element to determine how many electrons it can hold. Typically, the highest number of electrons that can fit in any given shell = 2n². To clarify, it depends on the atom. This equation provided can be used to find the number of the electrons but...
- Wed May 30, 2018 9:23 pm
- Forum: Lewis Structures
- Topic: Lewis Structures with Transition Metals
- Replies: 2
- Views: 4032
Re: Lewis Structures with Transition Metals
to find the valence electron of a transition metal I would try using the electron configuration, it would require you to use the (n-1) concept. For the energy levels you subtract one when you are working with transition metals. Then the amount of electrons in the last energy level would be your vale...
- Thu May 24, 2018 6:21 pm
- Forum: Lewis Structures
- Topic: Finding the central element on the Lewis structure
- Replies: 4
- Views: 1695
Re: Finding the central element on the Lewis structure
Usually you can follow the rule on F O N Cl (Br I). Electronegativity increases from right to left, meaning that it is less likely to be in the center of the Lewis structure. If the molecule they asked for was ONF, because out of the three elements N is the least electronegative, it would be in the...
- Thu May 24, 2018 12:53 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polarizing power vs polarizability
- Replies: 2
- Views: 564
Re: Polarizing power vs polarizability
To explain the concept simply rather than the process and add to the answer above, I understand that polarization power is the ability of a cation to distort an anion (has to do ore with the cation) while polarizability is how an anion becomes polarized by a cation (has to do more with the anion). S...
- Wed May 23, 2018 11:02 am
- Forum: Lewis Structures
- Topic: Finding the central element on the Lewis structure
- Replies: 4
- Views: 1695
Finding the central element on the Lewis structure
I am still confused on how you find which element goes in the center when doing lewis structure. For example in question 3.51 the book asks for 2 lewis structures for HClO, in the solution one of the structures has O in the center and the other has Cl in the center. I don't understand how to get the...
- Wed May 23, 2018 10:58 am
- Forum: Lewis Structures
- Topic: Radical HW 3.59
- Replies: 6
- Views: 813
Re: Radical HW 3.59
I don't really understand how you all are finding radicals. For example question 3.55 asks us to identify which of the following are radicals: NO2-, CH3, OH, CH2O.
How do you know which are radicals?
How do you know which are radicals?
- Mon May 14, 2018 8:06 am
- Forum: General Science Questions
- Topic: Conceptual Questions
- Replies: 4
- Views: 680
Re: Conceptual Questions
I think it is helpful to just give yourself time to process more conceptual questions. If there is such a topic, it helps to just sit and think it out, even explain it to yourself or someone else. Drawing it out also seems really helpful, I think I will try it next time!
- Mon May 14, 2018 8:01 am
- Forum: Lewis Structures
- Topic: resonance
- Replies: 6
- Views: 702
Re: resonance
Thanks so much: the replies really cleared it up! A follow-up question: if the correct lewis structure is a combination of the possible "correct" ones, why would we still need to calculate formal charge? Is that just to determine the result of resonance? Resonance states that some Lewis s...
- Mon May 14, 2018 7:55 am
- Forum: Lewis Structures
- Topic: Octet Rule [ENDORSED]
- Replies: 3
- Views: 638
Re: Octet Rule [ENDORSED]
I believe starting at the d orbitals, this rule no longer applies because these elements can hold more than 8 electrons (same with p and f). I think the TA's also explained it as the elements on the 3rd row or lower that break this rule, so you can see it like that on a test.
- Fri May 11, 2018 8:23 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: H-Atom
- Replies: 3
- Views: 516
Re: H-Atom
Just to explain what the previous comments stated, in class we only use the constant with hydrogen, this is because the model only works with a one electron system (such as hydrogen, but it would work for others with one electron only).
- Fri May 11, 2018 8:16 am
- Forum: Quantum Numbers and The H-Atom
- Topic: Midterm Question
- Replies: 13
- Views: 1424
Re: Midterm Question
Endri Dis 1J wrote:So to clarify, we didn't need include ms which is just the basic -1/2and +1/2?
No, I believe we didn't need to include ms (-1/2and +1/2)
- Fri May 11, 2018 8:14 am
- Forum: Lewis Structures
- Topic: Ionic vs Covalent
- Replies: 5
- Views: 758
Re: Ionic vs Covalent
There are examples made easy on this site: http://www.kentchemistry.com/links/bond ... isDots.htm
It mainly focuses on ionic bonds so maybe it can help you identify them.
It mainly focuses on ionic bonds so maybe it can help you identify them.
- Fri May 04, 2018 8:41 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Pauli Exclusion Principle
- Replies: 1
- Views: 284
Pauli Exclusion Principle
Hund's rule explains when the electrons start pairing on the orbitals, but does anyone understand why the Pauli exclusion principle limits this to 2 electrons?
- Fri May 04, 2018 8:34 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Hund's Rule [ENDORSED]
- Replies: 6
- Views: 1157
Re: Hund's Rule [ENDORSED]
I agree with everyone about but put easier The hund’s rule basically just says that electrons will enter the empty orbitals first, then start pairing when all are full.
- Fri May 04, 2018 8:25 am
- Forum: Trends in The Periodic Table
- Topic: Issues with 7th Edition Textbook
- Replies: 3
- Views: 472
Re: Issues with 7th Edition Textbook
I’m not sure about matching the questions, but if you don’t want to spend a lot on another textbook you could just buy the pdf version, it’s kind of difficult to get to the pages you need quickly though since you have to scroll through a lot.
- Fri May 04, 2018 8:22 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: d block electron configuration
- Replies: 5
- Views: 1356
Re: d block electron configuration
Also why do cations in the d block lose their s orbital electrons before their d orbital electrons? I think it has to do with the energy of the 3d orbitals being slightly less than that of the 4s. This link explains a lot: https://www.chemguide.co.uk/atoms/properties/3d4sproblem.html Hope that help...
- Fri Apr 27, 2018 8:18 am
- Forum: DeBroglie Equation
- Topic: 1.33 using De Broglie
- Replies: 3
- Views: 456
1.33 using De Broglie
I was trying to do 1.33 on my own, but I got confused and looked at the solutions manual which confused me more. Does anyone understand how it is solved in the solutions manual, I now get how they got the equations but where did they get those numbers? (for part A)
- Fri Apr 27, 2018 8:09 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Wavelengths and their corresponding electromagnetic spectrum
- Replies: 2
- Views: 387
Re: Wavelengths and their corresponding electromagnetic spectrum
There is another question like this already posted, according to people who already took the test you should know x rays< UV< infrareds < microwaves.
Someone also mentioned to know red light= 700nm and violet= 400nm
Someone also mentioned to know red light= 700nm and violet= 400nm
- Fri Apr 27, 2018 7:57 am
- Forum: Photoelectric Effect
- Topic: Photoelectric Effect Module Question [ENDORSED]
- Replies: 5
- Views: 754
Re: Photoelectric Effect Module Question [ENDORSED]
According to the graphics on photoelectric effect the light is ultraviolet.
- Thu Apr 19, 2018 8:55 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Lyman and Balmer Series
- Replies: 3
- Views: 467
Lyman and Balmer Series
The Lyman and Balmer series were very briefly mentioned in lecture, I did not understand what each meant. All I was able to get was that the Lymer series somehow has to do with UV and the Balmer with inferred light. Does anyone remember what these terms mean?
- Thu Apr 19, 2018 8:50 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: work example in class from April 16
- Replies: 2
- Views: 200
work example in class from April 16
I am looking at my notes and in one of the examples from class, our professor wrote E subscript 4= 1/16 x hR, can someone explain where the 1/16 came from?
- Thu Apr 19, 2018 8:41 pm
- Forum: Photoelectric Effect
- Topic: What is a vacuum?
- Replies: 7
- Views: 845
Re: What is a vacuum?
A vacuum is basically an empty space, as in there is no other molecules to affect the experiment. So in these vacuums gaseous pressure is much less than atmospheric pressure.
- Fri Apr 13, 2018 7:25 am
- Forum: Limiting Reactant Calculations
- Topic: actual vs. theoretical yield [ENDORSED]
- Replies: 6
- Views: 1583
Re: actual vs. theoretical yield [ENDORSED]
Adding on, theoretical yield is calculated using the amount of reactants to figure the maximum amount of product. This is because theoretical yield assumes best case scenario, that everything in the experiment will go perfectly planned but there is cases in real life where some of the reactants, for...
- Wed Apr 11, 2018 10:15 pm
- Forum: Balancing Chemical Reactions
- Topic: Balancing equations with fractions [ENDORSED]
- Replies: 13
- Views: 1643
Re: Balancing equations with fractions [ENDORSED]
The coefficients must be in whole numbers so you would have to multipy the whole equation (both sides, like in a math problem) by 2 to get rid of the fraction.
- Wed Apr 11, 2018 10:03 pm
- Forum: Empirical & Molecular Formulas
- Topic: Molecular to Empirical [ENDORSED]
- Replies: 12
- Views: 1949
Re: Molecular to Empirical [ENDORSED]
It is basically just like simplifying in math. Once you have the molecular formula you simplify using the greatest common number that you can divide by. For example lets say we have C6H12, then you can simplify by dividing what you have by 6 since both numbers are divisible by 6 to get CH6. Don't fo...
- Tue Apr 10, 2018 8:53 pm
- Forum: Empirical & Molecular Formulas
- Topic: Formula steps
- Replies: 4
- Views: 506
Re: Formula steps
I think it is easier to learn it as one process, either you can find the molecular formula using the empirical or the other way around. Finding the molecular formula first seems like a shorter process to me. First you multiply the given total mass by the percents of composition given, the mass you g...
- Tue Apr 10, 2018 8:31 pm
- Forum: Empirical & Molecular Formulas
- Topic: Rounding molar ratios
- Replies: 3
- Views: 12698
Re: Rounding molar ratios
When I practice these problems, I usually round to the nearest whole number when I get something that .90 or above, so far this has worked good for me and the person who replied before says rounding .70 and .8 may give you weird answers. I would suggest that if you are unsure the you should multiply...
- Tue Apr 10, 2018 8:21 pm
- Forum: Balancing Chemical Reactions
- Topic: Subscripts [ENDORSED]
- Replies: 6
- Views: 919
Re: Subscripts [ENDORSED]
The way I see it is as a normal math problem. In math when you have a number multiplying by the stuff in parenthesis you are supposed to distribute. Similarly when you have something like Mg(N3)2, you could see it in this way and distribute the 2, in other words you would multiply the number inside ...