Search found 37 matches
- Wed Jul 31, 2019 7:39 am
- Forum: Naming
- Topic: Naming/Coord Comp
- Replies: 4
- Views: 603
Re: Naming/Coord Comp
The cation ion is listed first. The ligands are listed in alphabetical order (not including their numerical prefixes) and then the metal ion and its charge and then the anion.
- Wed Jul 31, 2019 7:37 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Diff Sigma btw Pi Bonds
- Replies: 1
- Views: 376
Re: Diff Sigma btw Pi Bonds
If it is a single bond, it is a sigma bond, any additional bonds (the second bond within a double bond or the second and third bonds in a triple bond) are pi bonds. Sigma bonds occur end to end while pi bonds are side to side; sigma bonds allow atomic rotation and are therefore stronger than pi bond...
- Wed Jul 31, 2019 7:35 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Radical Atoms ?
- Replies: 1
- Views: 364
Re: Radical Atoms ?
A radical is a compound that has an unpaired electron. If the total number of valence electrons within a compound is an odd number, it will be a radical.
- Wed Jul 31, 2019 7:34 am
- Forum: Sigma & Pi Bonds
- Topic: Resonance [ENDORSED]
- Replies: 3
- Views: 787
Re: Resonance [ENDORSED]
I know a molecule has resonance when the central atom is bonded to 2 or more of the same element, but has different bonds (single, double, or triple) with the atoms. Since these atoms are the same element, which atom has which bond does not matter and the molecule can have resonance, alternating bet...
- Tue Jul 30, 2019 9:32 am
- Forum: Polyprotic Acids & Bases
- Topic: Spectator ions
- Replies: 3
- Views: 921
Spectator ions
How do we know whether or not something is a spectator ion?
- Mon Jul 29, 2019 9:01 am
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: PH Equations [ENDORSED]
- Replies: 1
- Views: 498
Re: PH Equations [ENDORSED]
For calculating the equilibrium constant, the concentration of the products go on top and the concentration of the reactants go on the bottom.
- Mon Jul 29, 2019 8:59 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Oxidation states
- Replies: 5
- Views: 655
Re: Oxidation states
For coordination compounds, based on the charge of the overall compound, you can figure out the oxidation state of the central ion based on the known charges of the ligands and ions. For example, [Pt (NH3)5 Cl] Br3 has no net charge, so you know that the sum of all the charges must be 0. NH3 has no ...
- Thu Jul 25, 2019 8:18 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: homework 9C7 7th edition
- Replies: 2
- Views: 499
Re: homework 9C7 7th edition
My reasoning for this problem was that the angle between the two NH2 molecules in part C is too large for both molecules to bond simultaneously.
- Wed Jul 24, 2019 8:57 am
- Forum: Bronsted Acids & Bases
- Topic: Fundamentals J #1
- Replies: 1
- Views: 459
Fundamentals J #1
For number #1 in section J, they ask to identify each compound as a Bronsted acid or base. NH3, HBr, KOH, H2SO3, and Ca(OH)2 I know that Bronsted acids are proton donors and bases are acceptors, but how do we identify that based on just their molecular formula? I feel like I am missing something obv...
- Wed Jul 24, 2019 8:35 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Chelating [ENDORSED]
- Replies: 2
- Views: 569
Chelating [ENDORSED]
How can we tell if a molecule can function as a chelating ligand?
- Wed Jul 24, 2019 8:20 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligand bonds
- Replies: 1
- Views: 415
Ligand bonds
How do we know how many times a ligand can bond to a central metal atom? For example, in the 6th edition textbook, problem 17.33b asks for the maximum number of bonds CO3(2-) can form simultaneously.
- Tue Jul 23, 2019 10:31 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Why is AX3E2 linear?
- Replies: 8
- Views: 1401
Re: Why is AX3E2 linear?
We base the electron pair geometry on the number of regions of electron density surrounding the central atom (5), so it is trigonal bipyramidal. For the molecular geometry, we look at the bonds specifically. The bonds between the 3 surrounding atoms with the central atom create a T-shaped geometry.
- Wed Jul 17, 2019 8:12 am
- Forum: Ionic & Covalent Bonds
- Topic: Dipoles
- Replies: 7
- Views: 1128
Re: Dipoles
Dipole-Dipole interactions occur when polar molecules are attracted to eachother's opposite charges. Hydrogen bonds are a type of dipole-dipole interaction and also rely on polarity
- Wed Jul 17, 2019 8:07 am
- Forum: Ionic & Covalent Bonds
- Topic: Order of electron loss in ion formation
- Replies: 4
- Views: 691
Re: Order of electron loss in ion formation
What about with the 3s/4d orbital exception? Does that apply here?
- Tue Jul 16, 2019 8:34 am
- Forum: Bond Lengths & Energies
- Topic: boiling and melting points
- Replies: 1
- Views: 414
boiling and melting points
What is the relationship between boiling points, melting points, and a molecule's size and bonds?
- Tue Jul 16, 2019 8:25 am
- Forum: Ionic & Covalent Bonds
- Topic: Covalent Bonds [ENDORSED]
- Replies: 3
- Views: 770
Re: Covalent Bonds [ENDORSED]
Unless the bonded atoms are the same element, it is likely that the covalent bond has ionic characteristics/some polarity, since different elements possess different electronegativities and will therefore unequally share electrons.
- Tue Jul 16, 2019 8:19 am
- Forum: Administrative Questions and Class Announcements
- Topic: Homework
- Replies: 1
- Views: 426
Homework
For the homework due this Thursday, do the 14 problems have to be from the "Molecular Shape and Structure" outline, or can they be from the "Chemical bonds" outline, since we will only get to shape and structure the day before the homework is due?
- Tue Jul 16, 2019 8:16 am
- Forum: Lewis Structures
- Topic: Aluminum and Boron [ENDORSED]
- Replies: 2
- Views: 670
Re: Aluminum and Boron [ENDORSED]
Boron and Aluminum need 5 electrons to complete an octet, however, they are exceptions to the octet rule because they are involved in lewis acid-base reactions. They can have a complete octet if another atom provides both electrons for a coordinate covalent bond. In such cases, the electron pair don...
- Tue Jul 16, 2019 8:09 am
- Forum: Formal Charge and Oxidation Numbers
- Topic: Difference between charge and formal charge [ENDORSED]
- Replies: 4
- Views: 901
Re: Difference between charge and formal charge [ENDORSED]
The formal charge is assigned to each individual atom and is the difference between the valence electrons it normally possesses and the electrons it possesses in the molecule (from bonds or lone pairs). Each atom in a molecule will have a formal charge, and the sume of their formal charges will make...
- Tue Jul 16, 2019 7:57 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Midterm Question 5C
- Replies: 1
- Views: 397
Midterm Question 5C
On the midterm, question 5C asks: Write the ground-state electron configuration for Cu+ and give the first two quantum
numbers for the last electron.
Could someone explain how you get the configuration [Ar]3d^10?
numbers for the last electron.
Could someone explain how you get the configuration [Ar]3d^10?
- Thu Jul 11, 2019 7:42 am
- Forum: Molarity, Solutions, Dilutions
- Topic: hw L1
- Replies: 2
- Views: 534
Re: hw L1
How you wrote out the chemical equation is a bit confusing, but in general, you can tell how many moles are being produced based on the ratios between the stoichiometric coefficients. For example, if there the stoichiometric coefficient for ClO2 is 6 and the stoichiometric coefficient for Br2 is 1, ...
- Wed Jul 10, 2019 8:30 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 6th edition 19b [ENDORSED]
- Replies: 2
- Views: 615
6th edition 19b [ENDORSED]
In the 6th edition, problem 19 part b asks for the electron configuration and number of unpaired electrons for Sn (4+). Can someone explain why the answer [Kr]4d^85s^2? Thank you
- Wed Jul 10, 2019 8:11 pm
- Forum: Lewis Structures
- Topic: Double Bonds [ENDORSED]
- Replies: 4
- Views: 737
Re: Double Bonds [ENDORSED]
For many molecules, there is more than one way to draw its lewis structure/ many places where you can draw a double bond. For example, for NO3-, there can be a double bond between any one of the oxygen atoms and the nitrogen atom. In actuality, this means that the true structure is more of a blend o...
- Wed Jul 10, 2019 8:08 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 6th edition chapter 3 problem 9
- Replies: 2
- Views: 401
Re: 6th edition chapter 3 problem 9
I had trouble with this question too, until I realized the subshells we were dealing with. With the 4s vs. 3d subshells, electron configurations do not follow the typical "protocol." It takes less energy for electrons to join the 4s orbital and also to leave it, so the +2 charge means that...
- Sun Jul 07, 2019 1:01 pm
- Forum: Properties of Light
- Topic: Class lecture
- Replies: 2
- Views: 471
Re: Class lecture
Hydrogen atoms are simpler models for quantum analysis because they only have one electron, allowing us to only analyze that singular electron and its behavior/energy levels
- Sun Jul 07, 2019 12:58 pm
- Forum: Photoelectric Effect
- Topic: Photo electric effect
- Replies: 7
- Views: 883
Re: Photo electric effect
If the experiment were not conducted within a vacuum, there would be other variables, such as other molecules, we would have to consider that could impact the results.
- Sun Jul 07, 2019 11:12 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Nodes
- Replies: 1
- Views: 379
Nodes
Do we need to know about angular vs. radial nodes and the formulas used to calculate how many of them an orbital has? If so, what distinguishes the two apart from eachother?
- Sun Jul 07, 2019 11:10 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: quantum numbers
- Replies: 1
- Views: 354
quantum numbers
What does it mean that m(l) is related to the orientation of an orbital? Could someone explain what m(l) really tells us?
- Sun Jul 07, 2019 11:09 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Atomic Orbitals [ENDORSED]
- Replies: 5
- Views: 850
Atomic Orbitals [ENDORSED]
Will we need to know about "spherical polar coordinates," which are mentioned in section 2.2 of the textbook?
- Wed Jul 03, 2019 9:14 am
- Forum: Photoelectric Effect
- Topic: kinetic energy of electron
- Replies: 8
- Views: 1098
Re: kinetic energy of electron
When the energy of the photon is equal to the threshold energy (energy needed to release an electron), then kinetic energy of the electron will equal 0. If the photon's energy was less than the threshold energy, an electron would not be released, and if the photon's energy was greater than the thres...
- Wed Jun 26, 2019 8:50 pm
- Forum: Properties of Light
- Topic: Light variables
- Replies: 3
- Views: 962
Light variables
Could someone please explain the different variables we measure when dealing with light and their relationships to one another? I remember frequency and wavelength, but think I am forgetting one or two? Thank you!
- Wed Jun 26, 2019 8:46 pm
- Forum: Limiting Reactant Calculations
- Topic: How do you approach question M1 in 6th edition book?
- Replies: 2
- Views: 493
Re: How do you approach question M1 in 6th edition book?
Since we are told hypochlorite is in excess, we know that ammonia is our limiting reactant. To find theoretical yield, first divide the 35 g of ammonia by ammonia's molar mass to convert the value to moles of ammonia. Luckily, the chemical equation is already balanced so we can see the stoichiometri...
- Wed Jun 26, 2019 8:36 pm
- Forum: Balancing Chemical Reactions
- Topic: Combustion Equation
- Replies: 21
- Views: 2653
Re: Combustion Equation
Lauren Huang 1H wrote:Sometimes nitrogen can be an added reactant and product of the equation.
Will this be something that comes up in 14A though? Or should we just assume oxygen and water for now?
- Wed Jun 26, 2019 8:34 pm
- Forum: Empirical & Molecular Formulas
- Topic: Butter Chicken
- Replies: 4
- Views: 550
Re: Butter Chicken
Should we expect these worksheets to generally be easier or harder than test material?
- Wed Jun 26, 2019 8:32 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: the mole
- Replies: 4
- Views: 542
Re: the mole
Density is equal to mass divided by volume. Using SI units, it is kilograms per cubic meter.
- Wed Jun 26, 2019 8:28 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Homework Problem G.13 in Fundamentals
- Replies: 3
- Views: 503
Re: Homework Problem G.13 in Fundamentals
This problem can be solved as long as we know that even if a solution is diluted, the amount of solute stays the same. The variable for the amount of solute is n and n can be calculated by multiplying molarity (M) times volume (v). Thus, knowing that n stays the same, M times v also stays the same. ...
- Wed Jun 26, 2019 8:20 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: G.5
- Replies: 3
- Views: 603
Re: G.5
For part A: First, I calculated the molar mass of the compound, which is 105.99 g/mol. Next, to convert this value to moles, I calculated 2.111 g divided by the molar mass (g/mol) so that grams cancel out and we are just left with moles. Now that we have the number of moles (.0199 moles), we can div...