Search found 31 matches
- Tue Jul 30, 2019 11:51 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Angles
- Replies: 2
- Views: 408
Re: Angles
Yes!
- Fri Jul 26, 2019 7:54 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Why is AX3E2 linear?
- Replies: 8
- Views: 1421
Re: Why is AX3E2 linear?
It actually a T- shaped molecule.
- Fri Jul 26, 2019 3:48 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3008818
Re: Post All Chemistry Jokes Here
A joke about Helium.
- Fri Jul 26, 2019 3:47 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3008818
Re: Post All Chemistry Jokes Here
A joke about photon.
- Fri Jul 26, 2019 3:13 pm
- Forum: Naming
- Topic: Fe------ferrate? [ENDORSED]
- Replies: 8
- Views: 1323
Re: Fe------ferrate? [ENDORSED]
Cyanido is the new name for cyanide, also, when the complex is negatively charged, the metal cation will need to add ate. Iron is an exception that it will change its name to ferrate.
- Fri Jul 26, 2019 3:09 pm
- Forum: General Science Questions
- Topic: Final Material
- Replies: 3
- Views: 808
- Fri Jul 26, 2019 3:05 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Oxidation states
- Replies: 5
- Views: 663
Re: Oxidation states
By reference to the periodic table, the Group 1 metals are more likely to lose an electron to become octet, then it has +1 oxidation state. However, because of relatively high ionization energy, the Group 7 non-metals will not lose electrons, instead, they usually gain an electron to become octet. T...
- Fri Jul 26, 2019 2:59 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: H-bonds [ENDORSED]
- Replies: 5
- Views: 864
Re: H-bonds [ENDORSED]
Yes.
- Fri Jul 26, 2019 2:58 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Naming coordination compounds
- Replies: 3
- Views: 511
Re: Naming coordination compounds
I think we should remember them.
- Wed Jul 24, 2019 11:27 pm
- Forum: Hybridization
- Topic: homework 2.45 7th edition
- Replies: 1
- Views: 396
Re: homework 2.45 7th edition
There is a double bond which consists of a pi and a sigma bonds present in C and O. For the sigma bond, since there are three electron densities, its hybirdization should be C2sp2-O2sp2. For the pi bond, since there is a unused electron in its 2p orbital, it will form a pi bond with C2p and O2p.
- Wed Jul 24, 2019 5:20 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Final
- Replies: 4
- Views: 592
Re: Final
Some questions in the final may come from the homework, like midterm.
- Wed Jul 24, 2019 5:14 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: edta
- Replies: 8
- Views: 1921
edta
How many bonds can an edta ligand bond to a metal cation?
- Tue Jul 23, 2019 7:47 pm
- Forum: Dipole Moments
- Topic: Effect of size [ENDORSED]
- Replies: 7
- Views: 1381
Re: Effect of size [ENDORSED]
This is because that increase the molecular mass will increase the number of electrons present in a molecule, its electron clouds will be more likely to be distorted(polariziability) which will lead to greater attraction.
- Tue Jul 23, 2019 7:38 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: name of molecule structure
- Replies: 4
- Views: 1573
Re: name of molecule structure
First, we count the electron densities which is 5 (4 bonding pairs and 1 lone pair). It has the electron geometry of trigonal bipyramidal. However, instead having this structure, having 4 bonding pairs and 1 lone pair is called seesaw.
- Tue Jul 23, 2019 7:33 pm
- Forum: Ionic & Covalent Bonds
- Topic: Dipoles
- Replies: 7
- Views: 1151
Re: Dipoles
Only polar bonds have dipoles, and only dipoles form the hydrogen bonds will form.
- Tue Jul 23, 2019 2:53 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3008818
Re: Post All Chemistry Jokes Here
Heisenberg was caught speeding. The cops pulled him over and asked "do you know how fast you were going? " Heisenberg says "No, but I can tell you exactly where I was!" The cops were like " you were going 120 mph in 80 mph zone!" Heisenberg says " Great! Now I am l...
- Tue Jul 23, 2019 2:47 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3008818
Re: Post All Chemistry Jokes Here
never trust atoms, they make up everything.
- Tue Jul 23, 2019 2:46 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3008818
Re: Post All Chemistry Jokes Here
When a chemist dies, they barium.
- Tue Jul 23, 2019 2:27 pm
- Forum: Lewis Structures
- Topic: Problem 2E13 (7th edition) part d
- Replies: 1
- Views: 363
Re: Problem 2E13 (7th edition) part d
Both answers are acceptable since both models have total electrons of 16, and each atoms in both models is being octet. I am not sure about which one has the priority, but in the case of formal charge, both central atom N have formal charge of +1 ,the first model has a -1 charge on oxygen and the se...
- Tue Jul 23, 2019 2:14 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: Test 2
- Replies: 1
- Views: 464
Re: Test 2
For the molecule on the left, each nitrogen atom with lone pair can form hydrogen bond with water, also each hydrogen bonded with nitrogen with partial positive charge (due to the electronegativity) will form hydrogen bond with oxygen atom in water. There are 5 nitrogen atoms with lone pair and part...
- Mon Jul 22, 2019 10:04 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Rotations and Shape
- Replies: 4
- Views: 681
Re: Rotations and Shape
No, we don't have to know.
- Sun Jul 21, 2019 5:32 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 3
- Views: 394
Re: Bond Angles
We need to identify the shape by using the models mentioned in class. For centain type of model, we have to name the angles of its typical examples. Therefore, we should be able to name the shape and some basic angles.
- Sun Jul 21, 2019 5:25 pm
- Forum: Hybridization
- Topic: Determining how many electron densities
- Replies: 5
- Views: 580
Re: Determining how many electron densities
A lone pair is also an electron density. Therefore, a molecule with 3 bonding pairs and 1 lone pair should have 4 electron densities.
- Sun Jul 21, 2019 5:23 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Polar v. Nonpolar
- Replies: 11
- Views: 2077
Re: Polar v. Nonpolar
First, a polar molecule must contain polar bonds. Then, if all polar bonds can cancel out it can be a nonpolar molecules, if cannot, it will become a polar molecule. To figure out whether all the dipoles can cancel out completely, you can use a vector diagram to see it clearly.
- Sun Jul 21, 2019 5:19 pm
- Forum: Hybridization
- Topic: Pi and Sigma Bonds
- Replies: 17
- Views: 1199
Re: Pi and Sigma Bonds
For a double bond, there will be one pi and one sigma, and one triple bond consists of two pi bonds and one sigma bond.
- Mon Jul 15, 2019 3:30 pm
- Forum: Lewis Structures
- Topic: Ionic Bond Structures [ENDORSED]
- Replies: 2
- Views: 627
Re: Ionic Bond Structures [ENDORSED]
I think that the lewis structure cannot be used to demostrate the ionic bond because the "-----" represents the sharing of electrons (it is the characteristic of the covalent bonding). However, we can still use the dots in lewis diagram to represents gaining or losing electrons for ions.
- Mon Jul 15, 2019 9:24 am
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polarizing Power [ENDORSED]
- Replies: 8
- Views: 1233
Re: Polarizing Power [ENDORSED]
Polarizing power is determined by the strength which a cation distorts the electron clould in the anion, and with greater polarizing power, that ionic compound would have more covalent characteristics.
- Tue Jul 09, 2019 10:25 pm
- Forum: Properties of Light
- Topic: VIdeo Module: Photoelectric effect question
- Replies: 2
- Views: 552
Re: VIdeo Module: Photoelectric effect question
In this case, the kinetic energy can just be calculated from 1/2mv2 since we already have velocity and mass (from the constant booklet)
- Tue Jul 09, 2019 10:17 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Test 1 number 7
- Replies: 4
- Views: 2677
Re: Test 1 number 7
Using the mass to calculate the moles of cisplatin first, then use the moles to divide the molarity ti get the volume. Next time you can figure out the relations by units.
- Fri Jun 28, 2019 11:11 am
- Forum: SI Units, Unit Conversions
- Topic: Limiting Reactants
- Replies: 5
- Views: 691
Re: Limiting Reactants
I believe that the professor doesn’t expect us to know in our course, but after we learn these compounds, the name should be known
- Fri Jun 28, 2019 11:07 am
- Forum: SI Units, Unit Conversions
- Topic: Use of Kelvin
- Replies: 6
- Views: 853
Re: Use of Kelvin
It is the lowest temperature we can reached