Search found 33 matches
- Mon Dec 03, 2018 12:39 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: AX3E
- Replies: 18
- Views: 3178
Re: AX3E
In order to really break this down to know that it is trigonal pyramidal, you must understand the notation used in VSEPR Model. A is the central atom X is the number of bonded atoms E is the number of lone pairs One example of a trigonal pyramidal shaped molecule is NH3. N is the central atom, there...
- Mon Dec 03, 2018 12:32 pm
- Forum: Amphoteric Compounds
- Topic: Examples
- Replies: 6
- Views: 575
Re: Examples
Some amphoteric examples we discussed in lecture are:
BeO, Al2O3, Ga2O3, SnO2, Sb2O5, and PbO2
BeO, Al2O3, Ga2O3, SnO2, Sb2O5, and PbO2
- Mon Dec 03, 2018 12:31 pm
- Forum: Bronsted Acids & Bases
- Topic: Bronsted Acids/Bases Vs. Arrhenius Acids/Bases
- Replies: 1
- Views: 304
Bronsted Acids/Bases Vs. Arrhenius Acids/Bases
In the fundamentals J portion of the 7th edition textbook it talks about Arrhenius Acids/Bases. I don't recall learning about those types during lecture. Does anybody know if we need to know this for the final exam and what are some key distinguishers between Arrhenius and Bronsted acids/bases? Than...
Re: Naming
Memorizing common polyatomic ion formulas as well as their chargers will only benefit you for the exam!
- Sat Dec 01, 2018 3:25 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Polar Molecules
- Replies: 12
- Views: 815
Re: Polar Molecules
Although looking at a molecule simply to determine whether or not it is polar or nonpolar, it is more accurate to use VESPR theory in order to deduce whether it is or not forsure.
- Sat Dec 01, 2018 3:23 pm
- Forum: Lewis Acids & Bases
- Topic: lewis acid and bases
- Replies: 3
- Views: 345
Re: lewis acid and bases
The structures does affect whether or not it is an acid or a base. The resonance of a molecule is what affects it due to the ranging kPa value.
- Wed Nov 28, 2018 4:45 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Transition Metals and their binding
- Replies: 1
- Views: 291
Transition Metals and their binding
During the lecture, it was stated how transition metals are often bound to cage-like molecules. Are there any other examples other than the porphyrin ligand one we went over in class? I am having trouble visualizing it.
- Tue Nov 27, 2018 2:50 pm
- Forum: Hybridization
- Topic: s-character
- Replies: 6
- Views: 2558
Re: s-character
To add on to what s-character is and how to determine how much s-character is present, triple bonds have more s-character than single bonds. The more s-character, the shorter and tighter the bond is.
- Fri Nov 16, 2018 8:55 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond strength
- Replies: 2
- Views: 268
Bond strength
What is the reasoning and how can we deduce why bond strength goes in this order:
lone-lone pair > lone-bonding pair > bonding-bonding pair
lone-lone pair > lone-bonding pair > bonding-bonding pair
- Fri Nov 16, 2018 8:54 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sulfite Ion and its Bond Angle
- Replies: 3
- Views: 438
Sulfite Ion and its Bond Angle
In class we discussed the sulfite ion SO3 2-. I still don’t understand why the bond angle would be 106 rather than 109.5. Can someone explain?
- Fri Nov 16, 2018 8:52 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Linear Shape of O2
- Replies: 4
- Views: 1093
Linear Shape of O2
I thought that linear shaped molecules can’t have dipole moments. How is O2 an exception to this?
- Fri Nov 09, 2018 12:35 pm
- Forum: Dipole Moments
- Topic: Bond Lengths
- Replies: 3
- Views: 419
Re: Bond Lengths
Bond lengths are given and in Angstrom units.
- Fri Nov 09, 2018 12:34 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular Shape
- Replies: 2
- Views: 302
Re: Molecular Shape
We started the molecular shape and structure topic and covered VSESPR models and a few shapes.
- Fri Nov 09, 2018 12:33 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Different Shapes
- Replies: 4
- Views: 346
Re: Different Shapes
In class we covered three important shapes so far. They are linear (180 degrees w/ 2 bonding pairs), trigonal planar (120 degrees w/ 3 bonding pairs), and tetrahedral (109.5 degrees w/ 4 bonding pairs).
- Fri Nov 09, 2018 12:29 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Trigonal Planar
- Replies: 8
- Views: 901
Re: Trigonal Planar
All molecule structures are 3D!
- Thu Nov 01, 2018 2:53 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Molar Mass
- Replies: 8
- Views: 1259
Re: Molar Mass
The units for molar mass are grams per mol.
- Thu Nov 01, 2018 2:36 pm
- Forum: Trends in The Periodic Table
- Topic: Trends in first ionization energies
- Replies: 3
- Views: 319
Trends in first ionization energies
What are the trends in first ionization energies throughout the periodic table?
- Thu Nov 01, 2018 2:33 pm
- Forum: Lewis Structures
- Topic: Drawing Lewis Structures
- Replies: 14
- Views: 1943
Re: Drawing Lewis Structures
When drawing Lewis structures, follow this format: 1) Count the number of valence electrons for each atom. 2) Count atom with lowest ionization energy as the central atom (H is never the central atom). 3) Arrange atoms symmetrically around central atom. 4) Calculate the formal charges so that they a...
- Fri Oct 26, 2018 11:10 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Isoelectronic Molecules
- Replies: 2
- Views: 296
Isoelectronic Molecules
I know we went over one example in lecture that displayed isoelectronic molecules. Can someone give another series of examples?
- Fri Oct 26, 2018 11:06 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Covalent Radius
- Replies: 2
- Views: 280
Re: Covalent Radius
Covalent radius is just the radius of two atoms (nonmetals) that are joined by covalent bonds.
- Fri Oct 26, 2018 11:02 am
- Forum: Trends in The Periodic Table
- Topic: Electron Affinity
- Replies: 8
- Views: 666
Re: Electron Affinity
In terms of electron affinity, there are patterns that you must recognize and memorize. As you go across a period, electron affinity increases. As you go down a group, electron affinity decreases.
- Wed Oct 17, 2018 12:43 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Atomic Radius
- Replies: 3
- Views: 357
Re: Atomic Radius
Covalent radius only pertains to atoms present in a covalent bond whereas atomic radius can be of any atom.
- Wed Oct 17, 2018 12:35 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Difference in orbitals
- Replies: 3
- Views: 335
Re: Difference in orbitals
F-orbitals have more complicated shapes, meaning that there are more lobes. Having more lobes means that there is a more complicated shape in regards to displaying itself on a plane.
- Wed Oct 17, 2018 12:16 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Orbital Notations
- Replies: 3
- Views: 299
Orbital Notations
We brushed upon this in class, but I just want to clarify.. Why are the subscripts in the d-orbitals squared? Is it because there are four lobes? For example One of the orbitals has an electron density distribution located along the x and y axis: d (subscript x^2 -y^2)
- Thu Oct 11, 2018 5:58 pm
- Forum: Administrative Questions and Class Announcements
- Topic: chem test tmrw
- Replies: 6
- Views: 656
Re: chem test tmrw
There is a page of formulas and a periodic table on the front of the test!
- Thu Oct 11, 2018 5:57 pm
- Forum: Properties of Light
- Topic: Unit conversion in 1B.5
- Replies: 1
- Views: 92
Re: Unit conversion in 1B.5
Ev (energy volts) =1.6 X 10^-19 J
- Thu Oct 11, 2018 5:54 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric Effect
- Replies: 3
- Views: 159
Re: Photoelectric Effect
They descend one level at a time since each level is discrete and not continuous.
- Thu Oct 11, 2018 5:44 pm
- Forum: Photoelectric Effect
- Topic: Work function
- Replies: 7
- Views: 522
Re: Work function
Work function, also known threshold energy, is the minimum energy required to release an electron.
- Wed Oct 10, 2018 2:28 pm
- Forum: Significant Figures
- Topic: Calculators
- Replies: 20
- Views: 1696
Re: Calculators
Based off of experience from taking the quiz today, calculators are not provided. They sell cheap ones at the bookstore!
- Thu Oct 04, 2018 8:33 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Molecular weight vs molar mass
- Replies: 3
- Views: 181
Re: Molecular weight vs molar mass
Molecular weight is the gravitational pull whereas mass is the quantity of matter.
- Thu Oct 04, 2018 8:28 pm
- Forum: Significant Figures
- Topic: Limiting Reactants
- Replies: 6
- Views: 563
Re: Limiting Reactants
Limiting reactant is the reactant with the least amount of mol produced.
- Thu Oct 04, 2018 8:26 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Finding the Molar Mass of a metal
- Replies: 2
- Views: 131
Re: Finding the Molar Mass of a metal
Also, to understand why it is calcium sulfide is because the subscript on OH is 2. By noticing the subscript you can deduce that the metal must be from the second group due to its charge.
- Wed Oct 03, 2018 2:06 pm
- Forum: Balancing Chemical Reactions
- Topic: Combustion Reactions.
- Replies: 8
- Views: 2915
Re: Combustion Reactions.
O2 will always be one of the reactants and the products will always be H2O and CO2.