Search found 51 matches
- Sun Dec 01, 2019 8:55 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination Number
- Replies: 6
- Views: 411
Re: Coordination Number
Coordination number is the number of ligands bonded to the central atom. The coordination number of Ba[FeBr4]2 is 4 since there are 4 ligands bonded to the Fe atom.
- Sun Dec 01, 2019 8:52 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligands
- Replies: 4
- Views: 411
Re: Ligands
A chelate is a complex with at least one ligand that forms a ring of atoms with the central metal atom in it.
- Sun Dec 01, 2019 8:46 pm
- Forum: Naming
- Topic: explain Coordination compound
- Replies: 5
- Views: 411
Re: explain Coordination compound
Coordination compound and complex can be used interchangeably. A coordination compound has a central atom or ion with ions or molecules attached by coordinate covalent bonds.
- Sun Dec 01, 2019 8:43 pm
- Forum: Biological Examples
- Topic: EDTA
- Replies: 8
- Views: 572
Re: EDTA
EDTA binds to metals and removes them from the bloodstream before it can bind to our DNA.
- Sun Dec 01, 2019 7:16 pm
- Forum: Lewis Structures
- Topic: Bent or Angular?
- Replies: 18
- Views: 1168
Re: Bent or Angular?
The terms "bent" and "angular" are interchangeable.
- Mon Nov 25, 2019 12:46 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Transition Metals
- Replies: 7
- Views: 464
Re: Transition Metals
All transition metals in the d-block form coordination compounds, but he speaks more about the first row in his lectures.
- Mon Nov 25, 2019 12:39 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Chelate
- Replies: 4
- Views: 323
Re: Chelate
A chelate complex contains at least one ligand that forms a ring of atoms that includes the central atom.
- Sun Nov 24, 2019 7:31 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Replacing H2O
- Replies: 2
- Views: 233
Re: Replacing H2O
NH3 can replace the H2O in the coordination compounds. There are a few that can replace the H2Os.
- Sun Nov 24, 2019 7:30 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: [PtCl2(en)2] 2+
- Replies: 3
- Views: 344
Re: [PtCl2(en)2] 2+
Since Pt attaches to the two Cl atoms then twice to the two (en), this makes six bonds to Pt.
- Sun Nov 24, 2019 7:27 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligands
- Replies: 5
- Views: 381
Re: Ligands
A ligand is a Lewis Base attached to the central atom or central ion in a d-metal complex.
- Sun Nov 17, 2019 1:13 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR notation
- Replies: 6
- Views: 428
Re: VSEPR notation
The VSEPR notation for CH2Cl2 is correct because there are four regions of electron density and the VSEPR notation for PCl3 is also correct because there are three atoms bonded with one lone electron pair.
- Sun Nov 17, 2019 1:10 am
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: AXE formula
- Replies: 32
- Views: 12249
Re: AXE formula
By knowing the central atom as well as how many lone pairs and bonded atoms there are, it can be deduced which shape the molecule is.
- Sun Nov 17, 2019 1:08 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 5
- Views: 378
Re: Bond Angles
A bond angle gets smaller due to lone pairs being stronger in repulsions than bonded atoms. Because the lone electron pairs repel more, there is less space between atoms, causing smaller bond angles.
- Sun Nov 17, 2019 1:05 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR notation
- Replies: 8
- Views: 554
Re: VSEPR notation
It is AX3 because there are three oxygen atoms attached to the central atom of nitrogen.
- Sun Nov 17, 2019 1:02 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: axial vs equitorial
- Replies: 3
- Views: 292
Re: axial vs equitorial
An axial lone pair is at the axis of the molecule while an equatorial lone pair lies at the equator. The lone pair at the equator is more favorable as it has lower energy and is more stable.
- Sat Nov 09, 2019 1:14 pm
- Forum: Dipole Moments
- Topic: Interaction Potential Energy
- Replies: 2
- Views: 182
Re: Interaction Potential Energy
The variable a1 represents the charge of the first ion (cation) while a2 is the charge of the second ion (anion).
- Sat Nov 09, 2019 1:06 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polar Covalent VS Ionic
- Replies: 11
- Views: 669
Re: Polar Covalent VS Ionic
Both the ionic and atomic radius trends decrease across a period and increase down a group due to the additions of energy levels. Across a period, the energy level stays the same and protons are being added, increasing the nuclear charge.
- Sat Nov 09, 2019 1:01 pm
- Forum: Bond Lengths & Energies
- Topic: de Broglie threshold
- Replies: 4
- Views: 367
Re: de Broglie threshold
Wavelength properties cannot be detected if it is less than 10^-15 m. This usually applies to the wavelengths of larger objects.
- Sat Nov 09, 2019 1:00 pm
- Forum: Dipole Moments
- Topic: Induced Dipole
- Replies: 4
- Views: 298
Re: Induced Dipole
When a polar molecule and non-polar molecule interact, the electrons are rearranged so as to create partial negative and partial positive charges that cause the induced dipole.
- Sat Nov 09, 2019 12:57 pm
- Forum: Ionic & Covalent Bonds
- Topic: Bond Strength
- Replies: 12
- Views: 1090
Re: Bond Strength
Since covalent bonds only have partial charges, ionic bonds are stronger due to larger differences in electronegativity.
- Mon Nov 04, 2019 12:12 am
- Forum: Dipole Moments
- Topic: Dipole Arrow
- Replies: 5
- Views: 271
Re: Dipole Arrow
In general, the arrow points to the negative dipole while the other end of the arrow has another line drawn perpendicular so as to make a + sign, indicating the positive dipole.
- Mon Nov 04, 2019 12:09 am
- Forum: Electronegativity
- Topic: Ionic or covalent?
- Replies: 17
- Views: 829
Re: Ionic or covalent?
Ionic compounds usually have charges and include metals with nonmetals, while covalent compounds are mostly nonmetals.
- Mon Nov 04, 2019 12:03 am
- Forum: Formal Charge and Oxidation Numbers
- Topic: formal charge
- Replies: 7
- Views: 443
Re: formal charge
I think you should only solve formal charge when the question asks or if there's resonance and you want to find the most stable structure.
- Mon Nov 04, 2019 12:00 am
- Forum: Lewis Structures
- Topic: Valence Electrons
- Replies: 2
- Views: 156
Re: Valence Electrons
Since the outermost shell of Cu only has one electron in 4s1, then there is only 1 valence electron.
- Sun Nov 03, 2019 11:58 pm
- Forum: Resonance Structures
- Topic: Resonance structures
- Replies: 6
- Views: 530
Re: Resonance structures
A resonance structure shows a compound with different electron arrangements.
- Sat Oct 26, 2019 5:55 pm
- Forum: Ionic & Covalent Bonds
- Topic: lewis structures for diff bonds
- Replies: 5
- Views: 186
Re: lewis structures for diff bonds
Lewis structures are drawn for both covalent and ionic bonds. Ionic structures would have the electrons and brackets of each ion with its charge. Covalent structures can be drawn with lines connecting each other as they share their electrons.
- Sat Oct 26, 2019 5:41 pm
- Forum: Ionic & Covalent Bonds
- Topic: Does the Octet Rule apply to Boron?
- Replies: 14
- Views: 886
Re: Does the Octet Rule apply to Boron?
Boron is more stable with 6 electrons and does not follow the octet rule.
- Sat Oct 26, 2019 5:32 pm
- Forum: Ionic & Covalent Bonds
- Topic: Resonance
- Replies: 12
- Views: 487
Re: Resonance
Compounds with resonance involve delocalized electrons, leading to fewer repulsions and more stability.
- Sat Oct 26, 2019 5:30 pm
- Forum: Ionic & Covalent Bonds
- Topic: ionization
- Replies: 8
- Views: 301
Re: ionization
There is less shielding and more protons after the first electron is removed. Therefore, more nuclear charge makes it more difficult for the next electron to be removed and will thus make the ionization energy higher.
- Sat Oct 26, 2019 5:25 pm
- Forum: Ionic & Covalent Bonds
- Topic: Meaning of Brackets
- Replies: 7
- Views: 371
Re: Meaning of Brackets
The brackets indicate the closest noble gas's electronic configuration so that the configuration of the given atom does not have to start from 1s.
- Sun Oct 20, 2019 11:00 pm
- Forum: DeBroglie Equation
- Topic: When to combine equations
- Replies: 10
- Views: 564
Re: When to combine equations
With a common variable, you can use substitution to make a new equation.
- Sun Oct 20, 2019 11:00 pm
- Forum: DeBroglie Equation
- Topic: When to combine equations
- Replies: 10
- Views: 564
Re: When to combine equations
With a common variable, you can use substitution to make a new equation.
- Sun Oct 20, 2019 10:54 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: What does the H mean?
- Replies: 9
- Views: 881
Re: What does the H mean?
The h is Planck's constant, which is 6.626x10^-34 J*s.
- Sun Oct 20, 2019 10:48 pm
- Forum: Properties of Electrons
- Topic: Photons
- Replies: 9
- Views: 344
Re: Photons
If a photon does not have enough energy to eject an electron, the electron stays in the same energy level.
- Sun Oct 20, 2019 10:46 pm
- Forum: Properties of Light
- Topic: homework 1A.3
- Replies: 8
- Views: 295
Re: homework 1A.3
As seen in the equation speed of light=(frequency)(wavelength), frequency and wavelength have an inverse relationship. Thus, when the frequency decreases, the wavelength increases.
- Sun Oct 20, 2019 10:33 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Order or orbitals
- Replies: 5
- Views: 234
Re: Order or orbitals
When writing electronic configurations, the order goes from lowest energy to highest energy, and the 3d orbital has lower energy than 4s, so the 3d goes before the 4th level.
- Mon Oct 14, 2019 2:16 am
- Forum: DeBroglie Equation
- Topic: De Broglie's Equation
- Replies: 17
- Views: 626
Re: De Broglie's Equation
The equation requires an object that has mass, but light does not have that. Thus, light cannot be used in this equation.
- Mon Oct 14, 2019 2:14 am
- Forum: DeBroglie Equation
- Topic: Diffraction
- Replies: 4
- Views: 273
Re: Diffraction
Diffraction causes radiation to bend as it goes through an edge.
- Mon Oct 14, 2019 2:06 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Rydberg equation [ENDORSED]
- Replies: 73
- Views: 9124
Re: Rydberg equation [ENDORSED]
The Rydberg equation is 1/λ = RZ2(1/n1^2 - 1/n2^2), with R=Rydberg constant and Z=atomic number of the atom. This is used to find the light's wavelength of an electron moving through different energy levels.
- Mon Oct 14, 2019 1:58 am
- Forum: Properties of Light
- Topic: When to use the Planck's Constant?
- Replies: 6
- Views: 352
Re: When to use the Planck's Constant?
Planck's constant can be used to find the energy emitted or absorbed at different levels with En = -hR / n^2. This has n= energy level, h=Planck's constant, R=constant value, and E=energy.
- Sun Oct 13, 2019 10:42 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric Effect
- Replies: 3
- Views: 177
Re: Photoelectric Effect
The photoelectric has to do with the emission of electrons in reference to the absorption of photons, while the atomic spectra indicate the wavelength to which atoms emit light.
- Mon Oct 07, 2019 5:45 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Symbols for Molarity
- Replies: 8
- Views: 1303
Re: Symbols for Molarity
Yes, c and M can be used interchangeably because c refers to concentration and M refers to molarity.
- Mon Oct 07, 2019 5:28 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Dilutions
- Replies: 3
- Views: 262
Re: Dilutions
In finding the molarity, you would have to convert the volume to Liters in order to solve, because that is the unit of the volume in the formula of molarity.
- Mon Oct 07, 2019 5:19 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: G 23
- Replies: 1
- Views: 107
Re: G 23
To find the concentration of chloride ions in the solution, you would have to find the moles of 0.50g NaCl and 0.30g KCl then find the sum of those moles. From there, you would divide this sum by 0.100 L to find the concentration of the chloride ions.
- Mon Oct 07, 2019 5:15 pm
- Forum: Limiting Reactant Calculations
- Topic: thereotical yield
- Replies: 5
- Views: 217
Re: thereotical yield
Typically, the theoretical yield is based on grams unless asked otherwise. It is a rare case for the theoretical yield to be in moles or any other unit.
- Mon Oct 07, 2019 5:13 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Week 2 Homework Problems [ENDORSED]
- Replies: 67
- Views: 7839
Re: Week 2 Homework Problems [ENDORSED]
There was an email sent out that said homework for Week 2 can cover both review topics and the quantum world. I would prefer to focus more on the review topics as there is a test coming up during discussions.
- Wed Oct 02, 2019 11:42 am
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Homework Problem E.15
- Replies: 4
- Views: 204
Re: Homework Problem E.15
For this question, you would have to subtract the mass of (OH)2 from 74.10 g/mol to find the mass of M and see which element has the closest mass to that of M. After figuring out what element M is, add the molar mass of M and S to get the answer.
- Wed Oct 02, 2019 11:39 am
- Forum: Molarity, Solutions, Dilutions
- Topic: Dilution and Molarity Questions
- Replies: 8
- Views: 667
Re: Dilution and Molarity Questions
In answering these types of problems, I write down the values that are given to me and think about the formula I can use, which is usually M1xV1=M2xV2. I figure out the desired molarity and volume as well as the initial molarity and volume, then plug those values into the formula.
- Wed Oct 02, 2019 11:36 am
- Forum: Empirical & Molecular Formulas
- Topic: Mass % Composition
- Replies: 7
- Views: 641
Re: Mass % Composition
You would have to find the mass of the entire molecule as well as the masses of each element. Divide each element's mass by the entire molecule's mass and multiply each by 100% to get the mass percent composition.
- Wed Oct 02, 2019 11:28 am
- Forum: SI Units, Unit Conversions
- Topic: Question about Showing Work
- Replies: 22
- Views: 1073
Re: Question about Showing Work
Would it also be necessary to write out the formula being used in answering a question?
- Wed Oct 02, 2019 11:25 am
- Forum: Significant Figures
- Topic: All students read this sig fig post [ENDORSED]
- Replies: 170
- Views: 35076
Re: All students read this sig fig post [ENDORSED]
Evamae Bayudan 1B wrote:Will we be penalized for putting extra significant figures?
I think we will be penalized since adding extra significant figures or removing them will result in an inaccurate response in the context of the question.