In order to identify a strong acidic solution (hydrochloric acid), can we apply the "strong, short bonds are less acidic" and "weak, long bonds are more acidic."
Would image b be correct since the atoms are all over the place?
Search found 31 matches
- Thu Jun 07, 2018 6:39 pm
- Forum: Lewis Acids & Bases
- Topic: HW J9
- Replies: 2
- Views: 494
- Thu Jun 07, 2018 6:09 pm
- Forum: Bronsted Acids & Bases
- Topic: Bronsted vs Lewis acids
- Replies: 3
- Views: 687
Re: Bronsted vs Lewis acids
A Bronsted acid is a proton donor while a Lewis acid accepts an electron pair.
A Bronsted base is a proton acceptor while a Lewis base donates an electron pair.
Hope this helped!
A Bronsted base is a proton acceptor while a Lewis base donates an electron pair.
Hope this helped!
- Thu Jun 07, 2018 5:50 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Award Pictures [ENDORSED]
- Replies: 5
- Views: 649
Re: Award Pictures [ENDORSED]
Award Recipient!
- Thu Jun 07, 2018 5:44 pm
- Forum: General Science Questions
- Topic: Final [ENDORSED]
- Replies: 10
- Views: 1412
Re: Final [ENDORSED]
I believe the final is cumulative so I'm sure there will be a balance between pre-midterm and post-midterm material. This is what I heard from my UA. Correct me if I'm wrong.
- Thu May 31, 2018 9:39 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: HW 4.13 part c
- Replies: 4
- Views: 454
Re: HW 4.13 part c
The solutions manual states that there are other possible resonance forms so yours is right and the solutions manual's as well. It's just about which one is more stable but I don't think that matters when it comes to the shape of the molecule and bond angles.
- Thu May 31, 2018 9:19 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR AXE
- Replies: 4
- Views: 542
Re: VSEPR AXE
E in the VSEPR Formula is always referred to as 'PAIRED' lone electrons so I doubt you would put anything if there was a radical.
Hope this helped!
Hope this helped!
- Thu May 31, 2018 9:06 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: 4.3 Homework
- Replies: 3
- Views: 707
Re: 4.3 Homework
Since the lone pair is on nitrogen and not the central atom (carbon), then the shape is linear for HCN. CH2N2 is tetrahedral because carbon (center atom) is bonded with 4 atoms. If it was trigonal planar, carbon would've been bonded with three atoms.
- Wed May 23, 2018 10:28 pm
- Forum: Lewis Structures
- Topic: H Formal Charge
- Replies: 4
- Views: 513
Re: H Formal Charge
I understand the formal charge would be zero. However, why don't we label it as such? When other atoms in the Lewis structure have a formal charge of zero we indicate it. Would it be wrong to include it? I don't think it'll be wrong to include it. If you feel like you have to include it, go for it!...
- Wed May 23, 2018 10:02 pm
- Forum: Lewis Structures
- Topic: Homework 3.39 part b
- Replies: 2
- Views: 408
Re: Homework 3.39 part b
Find the valence electrons for each atom and add them together. This will be the amount of electrons that should be present in the lewis structure of the molecule. Follow the octet rule (although there are some exceptions such as radicals), check formal charge, and go about making single, double, or...
- Wed May 23, 2018 9:54 pm
- Forum: Ionic & Covalent Bonds
- Topic: negative charges and lewis structures
- Replies: 3
- Views: 461
Re: negative charges and lewis structures
The outside charge is the charge of the whole molecule. This charge can be found by calculating the formal charge of every atom in the molecule and adding them together.
Hope this helped!
Hope this helped!
- Thu May 17, 2018 7:31 pm
- Forum: Lewis Structures
- Topic: Finding a Lewis Structure with the Lowest Energy
- Replies: 5
- Views: 639
Re: Finding a Lewis Structure with the Lowest Energy
What I do is make sure that every atom satisfies the octet rule and then calculate the formal charge, so I guess you can say it's mostly trial and error.
Hope this helped!
Hope this helped!
- Thu May 17, 2018 7:06 pm
- Forum: Lewis Structures
- Topic: HW 3.49 Part E
- Replies: 1
- Views: 263
HW 3.49 Part E
How do we know which atom receives the extra electron when a molecule has a negative charge. For example, on the homework problem 3.49 part e, we need to draw the lewis structure for CN- How do we know if carbon or nitrogen will receive that added electron? Does this have to do anything with electro...
- Thu May 17, 2018 6:53 pm
- Forum: Electronegativity
- Topic: Relationship between Electronegativity and Ionization Energy
- Replies: 4
- Views: 3154
Re: Relationship between Electronegativity and Ionization Energy
I agree with Nandhini 1G. I believe that if an element has low ionization energy, it should also have low electronegativity since those trends are the same on the periodic table.
- Wed May 09, 2018 9:52 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: question 8 week 5
- Replies: 1
- Views: 427
Re: question 8 week 5
a) Divide the 4.00 g of salt by the molar mass of CaCl2 (110.98 g/mol) = 0.036 mol of CaCl2. Since we only want the concentration of chloride ions, we multiply 0.036 mol of CaCl2 by the 2 moles of chloride ions which gives us 0.072 mol Cl/1 L. Concentration of chloride ions is 0.072 M. b) The total ...
- Wed May 09, 2018 9:18 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Ni3+
- Replies: 3
- Views: 8018
Re: Ni3+
I'll still explain it, just in case someone else is confused: Nickel's (Ni) electron configuration is: [Ar] 3d^8 4s^2 Ni3+ means removing 3 electrons and when we do this, we have to take the electrons off from the highest energy, in this case, 4s. Since you can only take 2 electrons away from 4s, we...
- Wed May 09, 2018 9:05 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Question 7 week 5
- Replies: 1
- Views: 625
Re: Question 7 week 5
Molarity=moles of solute/volume of solution, so 0.30 M = 0.30 mol/1L. Since there are 5 liters after the nurse dilutes 1 L of the solution by adding 4 L of water, the equation becomes 0.30 mol/5 L= a concentration of 0.06 M. We then multiply this (0.06 mol/L) by 0.10 L (100 mL=0.10 L). The answer sh...
- Thu May 03, 2018 3:28 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Explanation to the answer of the question 2.31
- Replies: 4
- Views: 509
Re: Explanation to the answer of the question 2.31
I had the same question as to why 2d does not exist if 2s and 2p exist. Why does it stop at 2p and not continue?
- Thu May 03, 2018 3:18 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Clarification on Spin Quantum Number
- Replies: 4
- Views: 521
Clarification on Spin Quantum Number
I'm a bit confused about the spin quantum number in the sense of when we have to use it or state it? Does the up or down arrow affect the electrons in any way?
- Thu May 03, 2018 3:00 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: 2.29
- Replies: 9
- Views: 1171
Re: 2.29
Can someone explain part d from problem 2.29. since n=3 and l=2, I know that it is in the 3d shell. It then gives you the magnetic quantum number which is +1. The answer is 2 electrons, but I don't understand why it is 2 electrons. I thought the d sub shell could hold up to 10 electrons.
- Wed Apr 25, 2018 10:45 pm
- Forum: DeBroglie Equation
- Topic: When to use DeBroglie or Ek equation
- Replies: 7
- Views: 850
Re: When to use DeBroglie or Ek equation
On my notes, I have written that the DeBroglie equation does not apply to light since light doesn't contain mass.
- Wed Apr 25, 2018 10:33 pm
- Forum: Einstein Equation
- Topic: HW Problem 1.27
- Replies: 1
- Views: 357
Re: HW Problem 1.27
Since 1 W= 1 J/s and there are 32 W then you basically have 32 J/s. The problem is asking us for how many photons can be generated in 2 seconds. Therefore, we get 32*2= 64 J. In this case we will use the equation E=h*c/Lambda since we already have the wavelength (420 x 10^-9 m). Multiply Planck's co...
- Wed Apr 25, 2018 10:08 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Homework Questions for Week IV
- Replies: 3
- Views: 419
Re: Homework Questions for Week IV
The homework problems Dr. Lavelle sent us are to prepare us for test 2 and the topics that will show up on the test. However, you can still choose homework problems from another chapter (as long as we covered it in class).
- Thu Apr 19, 2018 9:17 pm
- Forum: Properties of Light
- Topic: Test 2 [ENDORSED]
- Replies: 4
- Views: 599
Test 2 [ENDORSED]
For test 2 and future tests/exams, are we suppose to memorize constants, conversions, or any formulas? Also for wavelength, which units are preferable, m or nm?
- Thu Apr 19, 2018 9:08 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Lyman and Balmer Series
- Replies: 3
- Views: 467
Re: Lyman and Balmer Series
I have the same question. Also, is there anyone that can explain problem 1.11 which asks "what is common to the lines within a series that makes grouping them together logical?"
- Thu Apr 19, 2018 9:00 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: work example in class from April 16
- Replies: 2
- Views: 200
Re: work example in class from April 16
The 1/16 comes from 1/4^2 which equal 1/16. This is done because the formula is E[n] = -hR/n^2 in order to not have that division sign, we can write it as E[n] = -1/n^2 * hR
Hope this helps!
Hope this helps!
- Thu Apr 12, 2018 3:00 am
- Forum: Properties of Light
- Topic: HW 1.5 [ENDORSED]
- Replies: 7
- Views: 791
HW 1.5 [ENDORSED]
The homework problem asks us to "arrange the following types of photons of electromagnetic radiation in order of increasing energy: y-rays, visible light, ultraviolet radiation, microwaves, x-rays" Are we suppose to look at an image/chart in order to figure this out or are we suppose to ca...
- Thu Apr 12, 2018 2:50 am
- Forum: Properties of Light
- Topic: HW 1.3 [ENDORSED]
- Replies: 12
- Views: 1735
Re: HW 1.3 [ENDORSED]
C is correct because the lower the frequency, the longer the wavelength; therefore, causing it to have a decrease in the slope (extent of the change).
- Thu Apr 12, 2018 2:06 am
- Forum: Properties of Light
- Topic: HW 1.7 (speed of light) clarification
- Replies: 4
- Views: 269
HW 1.7 (speed of light) clarification
In lecture, I know that Dr. Lavelle mentioned that the speed of light was 3.0 x 10^8 but on the solutions manual, it says 2.998 x 10^8
Does it matter which one we use? Would the latter one be more accurate or preferable?
Does it matter which one we use? Would the latter one be more accurate or preferable?
- Fri Apr 06, 2018 4:59 pm
- Forum: Empirical & Molecular Formulas
- Topic: Periodic Table Memorization [ENDORSED]
- Replies: 8
- Views: 863
Re: Periodic Table Memorization [ENDORSED]
No, we don't have to memorize the periodic table. I'm sure they will provide us with one or maybe put it on screen so the whole class can see it. If you need one, the UCLA Bookstore sells some. It is very nice to have your own copy for homework or tests!
- Fri Apr 06, 2018 4:32 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Which mass of oxygen should be used? [ENDORSED]
- Replies: 23
- Views: 3362
Re: Which mass of oxygen should be used? [ENDORSED]
I'm sure you can use 16 grams/mol since Dr. Lavelle has used that in lectures. There's not much difference between 15.99 grams/mol and 16 grams/mol so I would go for the 16 since I'm sure rounding is preferred.
- Fri Apr 06, 2018 1:08 pm
- Forum: SI Units, Unit Conversions
- Topic: Confusion about Significant Figures (F.5)
- Replies: 2
- Views: 385
Re: Confusion about Significant Figures (F.5)
I also did problem F. 5 and what I did was round to the hundredths place. My answer at the end came out to be 100.2% so I'm guessing that's not a problem. Just disregard the extra significant figures and just round, in my opinion. The answer will be close to 100% anyways.