Search found 38 matches
- Sat Dec 09, 2017 10:12 pm
- Forum: Amphoteric Compounds
- Topic: amphoteric compounds pH
- Replies: 1
- Views: 550
Re: amphoteric compounds pH
They will usually have a set pH but depending on how they act that pH can fluctuate. You do not need to know how to caclulate the pH of amphoteric molecules on the final though to my knowledge.
- Fri Dec 08, 2017 8:18 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Determining whether ligand is mono-, bi-, or polydentate
- Replies: 3
- Views: 676
Re: Determining whether ligand is mono-, bi-, or polydentate
You can't really do that but the best way in my opinion is to just look at how many N's there are because in an organic molecule they usually have a lone pair making them some form of a chelating complex
- Wed Dec 06, 2017 4:19 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: What is electron-withdrawing Power?
- Replies: 1
- Views: 644
What is electron-withdrawing Power?
I'm confused what this means exactly? Is electron withdrawing power the ability to pull an electron (aka electronegativity) and how does this make something more stable when it loses a proton?
- Mon Dec 04, 2017 9:17 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: 12.65
- Replies: 1
- Views: 449
12.65
I kinda get how they are determing whether each is an acid or a base, but idk if they are getting their info from somewhere to ensure that they are acids or bases. Especially for part d, how is KBr nuetral while KF is basic?
- Sun Dec 03, 2017 8:52 pm
- Forum: Sigma & Pi Bonds
- Topic: What is a localized and delocalized Bond?
- Replies: 5
- Views: 32449
What is a localized and delocalized Bond?
I have no idea what the terms mean to be honest. Is localized meaning that it is just sigma bonds?
- Sun Dec 03, 2017 8:50 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: K values
- Replies: 2
- Views: 410
Re: K values
The higher the K value, the stronger the acid dissociation. Remember that K determines how which way the reaction proceed and how much it proceeds in which direction. If the K is large, it proceeds in favorably in the forward direction and favors products. Therefore, K values >1 are in favor of prod...
- Wed Nov 29, 2017 6:01 pm
- Forum: Lewis Acids & Bases
- Topic: J19 [ENDORSED]
- Replies: 1
- Views: 332
J19 [ENDORSED]
How come the two reactants are forming strong acids? This doesn't make any sense to me? Is this just theoretical?
- Wed Nov 29, 2017 5:59 pm
- Forum: Bronsted Acids & Bases
- Topic: Difference between Complete equation and Net Ionic Equation? [ENDORSED]
- Replies: 1
- Views: 387
Difference between Complete equation and Net Ionic Equation? [ENDORSED]
So I am doing the J problems of acids and bases and I am confused on the difference between the complete equation and Net Ionic equation. I understand that the Net ionic equation. I can't tell when to exclude the chemicals that dissociate in water like Na+ or Cl-.
- Tue Nov 28, 2017 2:44 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 11.89 Part b
- Replies: 2
- Views: 443
11.89 Part b
Why are all the values divided by 100 when calculating the K. I understand how they got the stoichiometric coefficients by making an ICE chart but there is no info that I see that indicates that the kPa needs to be divided by 100.
- Sun Nov 26, 2017 9:00 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Symmetrical Molecules
- Replies: 3
- Views: 555
Re: Symmetrical Molecules
Yes; for example, CH2Cl is symmetrical about the C but the Cl is more electronegative resulting in a greater pull towards that location of the symmetrical shape. Therefore, the molecule is polar because there is distinct dipole moment on one side of the molecule.
- Sun Nov 26, 2017 8:58 pm
- Forum: Hybridization
- Topic: Hybridization
- Replies: 5
- Views: 680
Re: Hybridization
It allows the molecule to create more openings for bonds with other molecules that, as a result, have a lower overall energy and therefore more stable.
- Fri Nov 24, 2017 9:44 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Calculating K from manipulations of Equation
- Replies: 1
- Views: 1659
Calculating K from manipulations of Equation
Why do we square our K when we double our chemical equation? Similarly, why do we square root the K when we halve it as well?
- Fri Nov 24, 2017 9:39 am
- Forum: Ideal Gases
- Topic: 11.7 Part a
- Replies: 3
- Views: 537
11.7 Part a
Does anyone know why flask 3 is the flask that most resembles a reaction that has reached equilibrium because flask 3 and 4 look exactly the same to me in terms of molecules.
- Fri Nov 24, 2017 9:35 am
- Forum: Hybridization
- Topic: Hybridization of Single Bonded Oxygen
- Replies: 1
- Views: 441
Re: Hybridization of Single Bonded Oxygen
A single bonded oxygen is not hybridized because it has not converted to its lowest energy form. It has 2 open orbitals to open electrons with by default in its ground state, therefore making its first bonding unhybridized.
- Tue Nov 14, 2017 10:16 am
- Forum: Dipole Moments
- Topic: 4.25 part a
- Replies: 2
- Views: 389
4.25 part a
Ok so i understand that the dipoles in CH2Cl2 will point towards the Cl's because they are more electronegative and I see through structure how it can be polar. But doesn't it depend on where the Cl and H are placed in order to determine if it is polar. Because if the Cl are directly across from eac...
- Mon Nov 13, 2017 9:27 pm
- Forum: Electronegativity
- Topic: Isoelectronic [ENDORSED]
- Replies: 11
- Views: 1440
Re: Isoelectronic [ENDORSED]
Atoms and ions have the same number of electrons. For example, Na+, Mg+2, F-, and Ne are isolectronic because they have the same amount of electrons.
- Sun Nov 12, 2017 8:29 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular shape vs Electron arrangement
- Replies: 2
- Views: 359
Re: Molecular shape vs Electron arrangement
Molecular shape is the shape of the molecule that is formed as a result of the electron arrangement. Electron arrangement is the position of the electrons on a molecule, which help to determine the shape due to repulsion forces. Thus, where the electrons are placed and how many are in that region de...
- Sun Nov 12, 2017 8:27 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 4
- Views: 605
Re: Bond Angles
Yes. It is put in the notes and basically all the homework questions relating to molecular shape so I'm pretty positive.
- Wed Nov 08, 2017 6:19 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Unpaired Electrons [ENDORSED]
- Replies: 7
- Views: 1022
Re: Unpaired Electrons [ENDORSED]
Draw out their orbitals by determining which subshell they are in. All the spots with only 1 "arrow" or electron in them is an unpaired electron.
- Tue Nov 07, 2017 10:14 am
- Forum: Student Social/Study Group
- Topic: DOWNLOAD PRACTICE MIDTERM HERE: Lyndon and Michael's session
- Replies: 7
- Views: 1673
Re: DOWNLOAD PRACTICE MIDTERM HERE: Lyndon and Michael's session
For number 1, how is the answer C24H42O21? Once I divided by the molar masses, I got 3.5967 moles of C, 6.2996 moles of H, and 3.15 moles of O. I divided all three by 3.15 to get the ratio 1.14 C, 2 H, and 1 O. Then I multiplied each number by 7 to get whole numbers and got C7H14O7 for the empirica...
- Tue Nov 07, 2017 10:06 am
- Forum: Ionic & Covalent Bonds
- Topic: oxidation state
- Replies: 3
- Views: 481
Re: oxidation state
Oxidation state is basically its charge or the state of an atom when it is not in its ground state (i.e. excited). Chlorine technically can have both positive and negative charges, although you will almost never see it with a positive oxidation state because it has such a large electron affinity and...
- Sat Nov 04, 2017 4:14 pm
- Forum: Lewis Structures
- Topic: Lewis Structure
- Replies: 4
- Views: 2915
Re: Lewis Structure
When looking at a molecule that is complex like this, you should follow the way in which the elements are ordered. So ClONO2 would have cl on the far left connected to an O, then with an NO2 ion connected to that O as well. This is a general rule I learned in AP chem because we have not learned how ...
- Thu Nov 02, 2017 9:16 am
- Forum: Lewis Structures
- Topic: Question 3.95
- Replies: 3
- Views: 396
Re: Question 3.95
It is forming an octet because each Carbon has 2 single bonds to each H and then 1 single bond to the central carbon and last 2 loose electrons. In total that is 8. The central Carbon however has 2 single bonds to 2 of the carbons and 1 double bond which is also 8. Therefore, they all satisfy the oc...
- Wed Nov 01, 2017 6:36 pm
- Forum: Lewis Structures
- Topic: Question 3.95
- Replies: 3
- Views: 396
Re: Question 3.95
Its the C in the CH2 that has only 4 valence electrons because you do not calculate formal charges on hydrogen atoms. Thus, the solution manual is correct in finding the lowest energy form of this molecule. A better way to look at this is to actually draw out the CH2's that are connect to the centra...
- Tue Oct 31, 2017 10:08 am
- Forum: Lewis Structures
- Topic: 3.39 Format in Answer Sheet
- Replies: 3
- Views: 491
3.39 Format in Answer Sheet
So I was pretty sure I understood how to write the lewis structure for each of these compounds. However, in the answer sheet the structures are drawn based on their ions and not together. I was wondering why and do we always do this for molecules that are composed of ions.
- Tue Oct 31, 2017 10:05 am
- Forum: Trends in The Periodic Table
- Topic: 2.81 – Oxygen Anomaly
- Replies: 2
- Views: 493
Re: 2.81 – Oxygen Anomaly
The reason for this anomaly is because oxygen is the first element in its sub-shell to have a paired electron in one of its orbitals. Thus, there is added repulsion between those two electrons. Therefore, Oxygen wants to lose that electron so it can be even in all of the orbitals which is lower ener...
- Tue Oct 24, 2017 9:45 pm
- Forum: Trends in The Periodic Table
- Topic: Problem 2.67 (c) and (d)
- Replies: 2
- Views: 324
Re: Problem 2.67 (c) and (d)
The reason that as you go up a group electron affinity is higher is because the atomic radius is smaller and thus the electron that it is trying to gain is more easily "pulled" into the element. Think of it as a smaller circle with a center that emits a pull on the electrons. If the circle...
- Mon Oct 23, 2017 9:35 pm
- Forum: Trends in The Periodic Table
- Topic: 2.67 part B
- Replies: 4
- Views: 548
2.67 part B
I understand that electron affinity is the energy released when an electron is added to an atom. I also understand the trend that as you go up and to the right of the periodic table electron affinity increased. Therefore, why does Carbon have a higher electron affinity than nitrogen?
- Mon Oct 23, 2017 9:33 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Sequen of Orbitals
- Replies: 4
- Views: 533
Re: Sequen of Orbitals
Yes we are supposed to put the 4s after the 3d. This is because we are going by increasing energy levels and the 3d subshell is lower energy. However, the 4s subshell fills up before the 3d which is why in highschool we learned to write it 4s3d.
- Tue Oct 17, 2017 8:03 pm
- Forum: DeBroglie Equation
- Topic: Wavelike Properties
- Replies: 3
- Views: 774
Re: Wavelike Properties
Well it really depends on the experiment. In the photoelectric effect, it acts as a particle because it needs a certain amount of energy to eject a photon. Thus, each particle of light must act like a particle. However, in the De Brogile experiment with the slits, it was observed that there were dif...
- Sat Oct 14, 2017 9:31 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: 1.57 [ENDORSED]
- Replies: 1
- Views: 290
1.57 [ENDORSED]
Lines in the Balmer series of the hydrogen spectrum are observed at 656.3, 486.1, 434.0, and 410.2nm. What is the wavelength of the next line in the series. Okay so I understand i need to use v=R(1/(n^2)- 1/(n^2)) (sorry its not perfect but you know the formula). I know the Balmer series starts n1=2...
- Thu Oct 12, 2017 5:38 pm
- Forum: *Black Body Radiation
- Topic: Black Body? [ENDORSED]
- Replies: 13
- Views: 2041
Re: Black Body? [ENDORSED]
A black body is any object that can absorb any incoming light. It is emits thermal heat due to its high absorption rate. However, if it gets too hot it starts to emit light (glow) from increased amounts of thermal radiation. Thus, all you really need to know is that it is a black body that can absor...
- Tue Oct 10, 2017 11:34 am
- Forum: DeBroglie Equation
- Topic: Chapter 1 #33 a [ENDORSED]
- Replies: 1
- Views: 347
Chapter 1 #33 a [ENDORSED]
The velocity of an electron that is emitted from a metallic surface by a photon is 3.6x10^3km/s.
a) What is the wavelength of the ejected electron?
I understand that I must use lambda=h/p and that p=mv. We have v and h is a constant so how do I get m?
a) What is the wavelength of the ejected electron?
I understand that I must use lambda=h/p and that p=mv. We have v and h is a constant so how do I get m?
- Mon Oct 09, 2017 6:33 pm
- Forum: Properties of Light
- Topic: Chapter 1 #3 c
- Replies: 1
- Views: 259
Chapter 1 #3 c
Which of the following happens when the frequency of electromagnetic radiation decreases? c) The extent of the change in the electrical field at a given point decreases. I am confused on how the question is worded to be honest. I understand that as frequency decreases the waves get wider but what do...
- Sun Oct 08, 2017 8:01 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Sig Figs [ENDORSED]
- Replies: 4
- Views: 744
Re: Sig Figs [ENDORSED]
There is a link on his site that "everything you want to know about sig figs." However, the basics are that numbers like 40 have only 1 sig fig because there is no decimal after as compared to 40. which is 2 sig figs. Furthermore, 3.02 is 3 sig figs while 3.020 is 4 sig figs even though th...
- Thu Oct 05, 2017 10:08 am
- Forum: Molarity, Solutions, Dilutions
- Topic: G13 Homework Problem
- Replies: 2
- Views: 496
Re: G13 Homework Problem
Ok so to start this problem, you need to see that the solution was .2M of just 1L of solution. However, the florist added 3 more L to the solution. Thus, there are 4L total in the final solution. Using M1V1=M2V2, you can plug in the variables and get your answer. You should get .05M for the 4L solut...
- Mon Oct 02, 2017 9:39 pm
- Forum: Balancing Chemical Reactions
- Topic: States of Matter in Chemical Equations
- Replies: 4
- Views: 757
Re: States of Matter in Chemical Equations
Technically, it is not correct to write chemical reactions without their state of matter. Writing the state of the substance allows us to determine what is formed and later on, espeicially if there is a dissociation. For example, Aluminum metal (Al (s)) is written different than a dissociated alumin...
- Mon Oct 02, 2017 2:24 pm
- Forum: Limiting Reactant Calculations
- Topic: M11 Part A [ENDORSED]
- Replies: 1
- Views: 411
M11 Part A [ENDORSED]
A reaction vessel contains 5.77 g of white phosphorous and 5.77 g of oxygen. The first reaction to take place is the formation of phosphorus (III) oxide: P4 + 3 O2 --> P4O6(s). If enough oxygen is present, the oxygen can react futher with this oxide to produce phosphorus (V) oxide: P4O6 + 2 O2 --> P...