Search found 20 matches

by Vincent Grospe 3C
Sat Dec 09, 2017 12:37 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligands sharing electrons
Replies: 1
Views: 190

Re: Ligands sharing electrons

Typically, ligands act as Lewis bases, electron-pair donating, and donate at least an electron pair to the metal, which essentially acts as a Lewis acid. In doing so, the ligand and metal have a coordinate covalent bond, where the two electrons come from one atom (ligand) yet are shared between two ...
by Vincent Grospe 3C
Fri Dec 08, 2017 12:47 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 12.27
Replies: 1
Views: 185

Re: 12.27

It is not being shown directly, but you will use the dilution equation M1V1 = M2V2 (you are solving for M2 in this case) in order to find the actual concentration of HCl, which will then give you the actual H30+ concentration.
by Vincent Grospe 3C
Sat Dec 02, 2017 1:40 pm
Forum: Naming
Topic: Naming with prefixes [ENDORSED]
Replies: 1
Views: 151

Re: Naming with prefixes [ENDORSED]

If the ligand already contains a Greek prefix (di, tri, tetra, etc.) or is polydentate, then you use the prefixes, bis, tris, tetrakis, etc. So if there were two ethylene di amine ligands in a complex ion, then you would use bisethylenediamine, because it already has the prefix “di” and it is a poly...
by Vincent Grospe 3C
Sat Dec 02, 2017 1:35 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Strong acid vs weak acid [ENDORSED]
Replies: 7
Views: 495

Re: Strong acid vs weak acid [ENDORSED]

On a side note, one defining feature to determine the difference is the number of arrows in the chemical formula (one means that it is a strong acid or base, while two half-headed arrows mean that it is a weak acid or base). It’s because the strong acid/base dissociates completely. However, someone ...
by Vincent Grospe 3C
Fri Nov 24, 2017 9:16 pm
Forum: Ideal Gases
Topic: 11.7 Part a
Replies: 3
Views: 347

Re: 11.7 Part a

Flasks 3 and 4 have the same composition of molecules, which means that the reaction has reached equilibrium. However, flask 3 occurred at an earlier time. Therefore, it’s safe to assume that at — specifically — flask 3, the reaction has reached equilibrium.
by Vincent Grospe 3C
Fri Nov 24, 2017 9:07 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: determining molecular shape?
Replies: 1
Views: 138

Re: determining molecular shape?

One always takes into account the number of lone pairs when trying to determine the VSEPR formula (“AXE” system and the molecular shape. Regarding VSEPR formula (AXE), A represents the number of central atoms (usually one), X represents the number of bonded atoms, and E represents the number of lone...
by Vincent Grospe 3C
Sat Nov 18, 2017 3:21 pm
Forum: Hybridization
Topic: 4.43
Replies: 1
Views: 158

Re: 4.43

S-character is the percentage of the s-orbitals. For instance, sp 3 has 25% s-character — 1 out of those 4 hybrid orbitals (total) is in the s-orbital. Therefore, the s-character increases as the number of p-orbitals (or p-character) decreases (33% s-character in sp 2 hybrid and 50% in sp hybrid). B...
by Vincent Grospe 3C
Thu Nov 16, 2017 4:07 pm
Forum: Dipole Moments
Topic: 4.29b
Replies: 2
Views: 166

Re: 4.29b

Two things to look at when comparing dipole moments of different molecules: first and most importantly, the resultant vector of all of the bond dipole moments (whether the dipole arrows cancel each other or all go in the same direction) based on the molecule’s structure as well as its bond angles an...
by Vincent Grospe 3C
Sat Nov 11, 2017 1:52 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Shape Memorization [ENDORSED]
Replies: 7
Views: 838

Re: Shape Memorization [ENDORSED]

@Michael In general, trigonal planar has a VSEPR formula of AX 3 — three bonded atoms to the central atom, while trigonal bipyramidal has a VESPR formula of AX 5 — five bonded atoms to the central atom. When I think of the word “planar”, I think one-dimensional or one plane. So the bonded atoms are ...
by Vincent Grospe 3C
Sat Nov 11, 2017 1:25 pm
Forum: Ionic & Covalent Bonds
Topic: Differences in polarity [ENDORSED]
Replies: 1
Views: 197

Re: Differences in polarity [ENDORSED]

The overall polarity (dipole moment) is equal to the “sum” of all bond polarities (in VSEPR models, the vectors). So yes, individual polarities are different from the overall polarity. And you can tell by drawing the VSEPR shapes of the molecule, drawing the dipole moments/arrows of all of the bonds...
by Vincent Grospe 3C
Sun Nov 05, 2017 12:11 am
Forum: Electronegativity
Topic: Comparing Electronegativity of Elements
Replies: 5
Views: 716

Comparing Electronegativity of Elements

Without an electronegativity chart, how can one compare electronegativities (which one is higher or lower) of elements that are diagonally close to each other (based on diagonal effect -- similar size)? Do we begin to focus on an element's closeness to fluorine, its period, or its group which impact...
by Vincent Grospe 3C
Sat Nov 04, 2017 11:43 pm
Forum: Lewis Structures
Topic: Lewis Structures for Molecules with Expanded Octet
Replies: 1
Views: 160

Lewis Structures for Molecules with Expanded Octet

Are there any specific rules for writing the Lewis structures of molecules with expanded octet as well as lone pairs (ex. BrF5 [square pyramidal, AX5E], SF4 [seesaw, AX4E], etc.)? Would it be wrong to write their Lewis structures just like their VSEPR models?
by Vincent Grospe 3C
Sat Oct 28, 2017 3:00 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Determining valence electrons for d-block elements [ENDORSED]
Replies: 3
Views: 4004

Re: Determining valence electrons for d-block elements [ENDORSED]

The valence electrons (outermost) for d-block elements (transition metals) are based on the number of electrons in the orbital with the highest principal quantum number, which is usually the ns-orbital [not the (n-1)d-orbital]. This goes back to Dr. Lavelle’s lectures on writing ground-state configu...
by Vincent Grospe 3C
Sat Oct 28, 2017 2:37 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: the quantum world [ENDORSED]
Replies: 3
Views: 298

Re: the quantum world [ENDORSED]

In regards to orbitals in the same principal quantum number or energy level (n)... Conceptually: the s-orbitals are closer to the nucleus, so the s-orbitals shields the atom and its positive charges (protons) better than p-orbitals, which explain why p-orbitals have higher energy. In a quantitative ...
by Vincent Grospe 3C
Sun Oct 22, 2017 3:12 pm
Forum: Quantum Numbers and The H-Atom
Topic: 4s 3d or 3d 4s?
Replies: 3
Views: 526

Re: 4s 3d or 3d 4s?

It is relative to the number of electrons that occupy each orbital. Usually before the 3d orbital is filled, electrons enter 4s orbital first. But, as you write configurations for transition elements (after the 4s orbital is occupied and configuration starts on the 3d orbital), the 3d goes before 4s...
by Vincent Grospe 3C
Sun Oct 22, 2017 2:50 pm
Forum: *Shrodinger Equation
Topic: HΨ=EΨ [ENDORSED]
Replies: 5
Views: 1007

Re: HΨ=EΨ [ENDORSED]

When Schrodinger’s equation is used, those three quantum numbers (n, l, ml) are used to label each wave function, which utilizes coordinates (r, theta, phi).
by Vincent Grospe 3C
Thu Oct 12, 2017 12:10 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Question about 1.15 [ENDORSED]
Replies: 3
Views: 376

Re: Question about 1.15 [ENDORSED]

Because you are determining initial and final n values, I would use the equation: v = R((1/n^2[lower quantum # -- n(1)=1,2,...] ) - (1/n^2[higher quantum # or n(2) = n = n(1) + 1,2...]). (Page 7 of the textbook) The lowest quantum number n(1) for hydrogen is n = 1, because it only has 1 proton/elect...
by Vincent Grospe 3C
Thu Oct 12, 2017 11:41 am
Forum: Photoelectric Effect
Topic: Q29 from PhotoElectric Effect Post-Module Assessment
Replies: 1
Views: 176

Re: Q29 from PhotoElectric Effect Post-Module Assessment

Yes, you use stoichiometry to convert kJ/mol to kJ/atoms using Avogadro's number.

There was another discussion thread about this on Chem Community for additional details: viewtopic.php?t=2344

Hope this helps!
by Vincent Grospe 3C
Thu Oct 05, 2017 12:37 pm
Forum: Limiting Reactant Calculations
Topic: L #39
Replies: 4
Views: 289

Re: L #39

When oxygen is alone (as well as hydrogen, nitrogen, chlorine, bromine, iodine, and fluorine -- HONClBrIF), it exists as a diatomic molecule -- hence, the subscript of 2. However, oxygen is apart of the compound -- it does not stand alone. So you would use the molar mass of one oxygen atom. However,...
by Vincent Grospe 3C
Thu Oct 05, 2017 12:23 pm
Forum: Empirical & Molecular Formulas
Topic: E29 Fundamentals
Replies: 3
Views: 289

Re: E29 Fundamentals

For Part B, you must use formula stoichiometry. For every mole of CuCl2 4 H20, there are two moles of Cl- ions (as well as 1 mole of Cu2+ and 4 moles of H20) based on the formula of the compound. Therefore, after finding the the number of moles of the compound, you will multiply it by 2 since the ra...

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