Search found 34 matches
- Mon Jun 11, 2018 9:50 pm
- Forum: Lewis Structures
- Topic: Radicals
- Replies: 1
- Views: 295
Radicals
How can we determine where the radical belongs in a Lewis Structure? For example, with ClO, the formal charges for each atom would be 0 if the radical were on the oxygen, but the correct structure has the radical on the chlorine. Why is this the case?
- Mon Jun 11, 2018 3:47 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Grading question
- Replies: 11
- Views: 1731
Re: Grading question
I think that it means 250 will be a C-, and then it is scaled up from there so if you have 350 it would be higher than that. I am not sure exactly how the curve works but that is my guess.
- Mon Jun 11, 2018 3:43 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Lone Pairs Affecting Bond Angles/Shape?
- Replies: 4
- Views: 787
Re: Lone Pairs Affecting Bond Angles/Shape?
Lone pairs affect bond angles by decreasing them due to increase repulsion. Because of this, any molecule with lone pairs will have bond angles that are slightly less than predicted.
- Mon Jun 11, 2018 3:01 pm
- Forum: Acidity & Basicity Constants and The Conjugate Seesaw
- Topic: weak acids
- Replies: 4
- Views: 682
Re: weak acids
I think in addition to knowing its properties, we generally need to know the weak acids that were discussed and how they behave.
- Sun Jun 03, 2018 5:30 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: HW 4.19
- Replies: 3
- Views: 532
HW 4.19
Predict the shapes and estimate the bond angles of (b) (CH3)2Be
Why is the shape tetrahedral if there are no lone pairs and only two bonds on the central atom?
Why is the shape tetrahedral if there are no lone pairs and only two bonds on the central atom?
- Sun Jun 03, 2018 4:30 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Naming Structures
- Replies: 8
- Views: 1012
Re: Naming Structures
Did you mean with the VSEPR model? If so, I do not think there is a trick but many are self-explanatory just by looking at the shape and the amount of bonds/lone pairs. (i.e. angular is similar to linear but slightly bent, T-shaped looks like a "T")
- Sun Jun 03, 2018 4:27 pm
- Forum: Dipole Moments
- Topic: Different types of dipole moments?
- Replies: 3
- Views: 493
Re: Different types of dipole moments?
I also am a bit confused as to which we need to know. There were many different types introduced in one lecture, but which ones should we know, and to what extent?
- Sun Jun 03, 2018 4:23 pm
- Forum: Octet Exceptions
- Topic: expanded octet
- Replies: 12
- Views: 2654
Re: expanded octet
We know that only the elements that are in Group 3 or below can form an expanded octet, as they have unfilled d-orbitals, which Groups 1 and 2 do not have.
- Mon May 28, 2018 11:19 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond angle
- Replies: 9
- Views: 977
Re: Bond angle
Do we find the lowest energy Lewis Structure to determine the bond angle?
- Mon May 28, 2018 6:13 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: HW 4.9
- Replies: 10
- Views: 1991
HW 4.9
What is the shape of an ICl3 molecule (iodine is the central atom)?
I thought that this molecule would have a trigonal planar arrangement, as it is AX3, but the answer key says that it is t-shaped. How could this be?
I thought that this molecule would have a trigonal planar arrangement, as it is AX3, but the answer key says that it is t-shaped. How could this be?
- Mon May 28, 2018 5:54 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond angles and lone pairs
- Replies: 4
- Views: 735
Bond angles and lone pairs
How can we determine whether or not there must be lone pairs from the bond angle?
- Sun May 20, 2018 6:07 pm
- Forum: Resonance Structures
- Topic: Radicals
- Replies: 13
- Views: 1438
Re: Radicals
I understand the concept of a radical, but when drawing Lewis structures, how do we decide which element has the unpaired electron?
- Sun May 20, 2018 5:13 pm
- Forum: Lewis Structures
- Topic: Where to put double bonds? [ENDORSED]
- Replies: 3
- Views: 433
Where to put double bonds? [ENDORSED]
In a problem like 3.41 (c): Write the Lewis structure for H2C(NH2)COOH, how do we know where to put the double bond?
- Sun May 20, 2018 5:00 pm
- Forum: Lewis Structures
- Topic: Friday's Lecture [ENDORSED]
- Replies: 4
- Views: 572
Re: Friday's Lecture [ENDORSED]
Will this material be on the exam this week, or is it only the material from Chapter 3?
- Fri May 18, 2018 11:58 am
- Forum: Ionic & Covalent Bonds
- Topic: 3.25
- Replies: 2
- Views: 347
3.25
On the basis of expected charges on the monatomic ions, give the chemical formula of each of the following compounds;
I am a bit confused about the elements in group 13 when it comes to determining their charges. Is there a pattern or a rule to follow here?
I am a bit confused about the elements in group 13 when it comes to determining their charges. Is there a pattern or a rule to follow here?
- Sun May 13, 2018 8:16 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Equation
- Replies: 3
- Views: 472
Re: Equation
It seems like the one you learned in high school may be a simplified version. Although it gives you the right answer, I feel like you should use the one that was given to us in class in terms of which will be more reliable.
- Sun May 13, 2018 7:12 pm
- Forum: Resonance Structures
- Topic: Bonds or Lone Pairs more important?
- Replies: 7
- Views: 1076
Re: Bonds or Lone Pairs more important?
I do not believe that there is a rule as to which comes first, but I would think that a double bond would come before an expanded octet.
- Sun May 06, 2018 7:47 pm
- Forum: Properties of Light
- Topic: Homework 1.15
- Replies: 2
- Views: 499
Homework 1.15
In the ultraviolet spectrum of atomic hydrogen, a line is observed at 102.6 nm. Determine the values of n for the initial and final energy levels of the electron. I understand in this problem that hydrogen gives us n=1, but to find the other energy levels in the solution it converts the wavelength i...
- Sat May 05, 2018 5:12 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Homework 2.55
- Replies: 2
- Views: 435
Homework 2.55
Give the notation for the valence-shell configuration (including the outermost d-electrons) of (b) Group 15 elements.
Why does the notation, ns^1np^3, not include d if some of the group 15 elements have d in their electron configuration?
Why does the notation, ns^1np^3, not include d if some of the group 15 elements have d in their electron configuration?
- Sat May 05, 2018 4:53 pm
- Forum: Ionic & Covalent Bonds
- Topic: Help on 2.43
- Replies: 3
- Views: 404
Re: Help on 2.43
Part e for 2.43 asks the electron configuration for Tungsten. How do we do the electron configuration for the f subshell, or do we not need to know this for the midterm?
- Sat May 05, 2018 4:51 pm
- Forum: Ionic & Covalent Bonds
- Topic: Midterm Topics [ENDORSED]
- Replies: 33
- Views: 4726
Re: Midterm Topics [ENDORSED]
Chapter 2 includes Zeff which we never went over in class, but is on the Chapter 2 homework. Will this topic be covered on the midterm?
- Sun Apr 29, 2018 9:24 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: The concept of Orbitals
- Replies: 12
- Views: 1055
Re: The concept of Orbitals
I agree with the above explanations, but I wanted to add that they show the electron density, which allows us to determine the probability of the electron being in a certain place.
- Sun Apr 29, 2018 9:10 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 2.37
- Replies: 2
- Views: 325
2.37
Which of the following are true for many-electron atoms? If false, explain why.
c) Electrons having l=2 are better at shielding than electrons having l=1.
Why exactly is this false and how does the value of Zeff work?
c) Electrons having l=2 are better at shielding than electrons having l=1.
Why exactly is this false and how does the value of Zeff work?
- Sun Apr 29, 2018 8:59 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 2.27 [ENDORSED]
- Replies: 4
- Views: 572
2.27 [ENDORSED]
Write the subshell notation and the number of orbitals having the following quantum numbers:
When it asks for the number of orbitals, is that the same as asking for the number of subshells? If not, how do you solve for this?
When it asks for the number of orbitals, is that the same as asking for the number of subshells? If not, how do you solve for this?
- Sun Apr 22, 2018 8:41 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test 2
- Replies: 3
- Views: 1170
Test 2
For the upcoming test, which equations will we be required to use? Which equations will be provided, and which should we memorize?
- Sun Apr 22, 2018 7:57 pm
- Forum: Properties of Light
- Topic: Homework 1.5
- Replies: 6
- Views: 603
Homework 1.5
Arrange the following types of photons of electromagnetic radiation in order of increasing energy: gamma rays, x-rays, visible light, ultraviolet radiation, microwaves. Why do gamma rays have the most amount of energy? If energy is proportional to frequency then how does the wavelength tell us about...
- Sun Apr 22, 2018 7:42 pm
- Forum: Properties of Light
- Topic: Question 1.3 [ENDORSED]
- Replies: 6
- Views: 729
Re: Question 1.3 [ENDORSED]
I have this question as well. The question asks: Which of the following happens when the frequency of electromagnetic radiation decreases? Explain your reasoning. Part c says: The extent of the change in the electrical field at a given point decreases.
- Sun Apr 15, 2018 9:04 pm
- Forum: Properties of Light
- Topic: Homework question 1.65
- Replies: 2
- Views: 340
Homework question 1.65
The energy required to break a C-C bond in a molecule is 348 kJ/mol. Will visible light be able to break this bond? If yes, what is the color of that light? If not, what type of electromagnetic radiation will be suitable? How would I go about solving this after converting this into Joules? How do I ...
- Sun Apr 15, 2018 8:57 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Memorizing equations [ENDORSED]
- Replies: 5
- Views: 843
Memorizing equations [ENDORSED]
To what extent do we need to have all of the different equations memorized? What will be provided to us on the exams?
- Sun Apr 15, 2018 8:42 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Solving 1.11 [ENDORSED]
- Replies: 3
- Views: 260
Re: Solving 1.11 [ENDORSED]
I agree with these responses, but another way to put it is that the principal quantum number is the same for each of these lines, so Lyman- n=1, Balmer- n=2, etc.
- Sun Apr 15, 2018 8:36 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Confusion about Atomic Spectroscopy [ENDORSED]
- Replies: 3
- Views: 423
Re: Confusion about Atomic Spectroscopy [ENDORSED]
From what I gathered, atomic spectroscopy is the idea that we can determine elemental compositions by looking at the electromagnetic radiation absorbed or emitted by certain atoms
- Mon Apr 09, 2018 11:56 am
- Forum: Molarity, Solutions, Dilutions
- Topic: G.5 Part A) Molarity [ENDORSED]
- Replies: 9
- Views: 952
Re: G.5 Part A) Molarity [ENDORSED]
I am still confused about how to do part A, as the solution in the book uses 1 mol Na2CO2 instead of Na2CO3. Where does this come from?
- Sun Apr 08, 2018 6:56 pm
- Forum: Balancing Chemical Reactions
- Topic: Memorizing the charges of ions
- Replies: 3
- Views: 409
Memorizing the charges of ions
Do we need to memorize the charge of each ion, or will this be provided?
- Sun Apr 08, 2018 6:01 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: E.15 [ENDORSED]
- Replies: 10
- Views: 1583
Re: E.15 [ENDORSED]
I had this question as well. I understand the explanation that 'M' is the variable, but would we have to know how to go about determining the sulfides for the test this week?