Search found 27 matches
- Sat Jun 09, 2018 10:14 pm
- Forum: Empirical & Molecular Formulas
- Topic: E3
- Replies: 2
- Views: 642
E3
The question is "In a nanotechnology lab you might have the capability to manipulate individual atoms. The atoms on the left are gallium atoms (molar mass 70 g/mol), those on the right are atoms of astatine (molar mass 210 g/mol). How many astatine atoms would the pan on the right have to conta...
- Wed Jun 06, 2018 5:51 pm
- Forum: Hybridization
- Topic: 4.43
- Replies: 1
- Views: 421
4.43
The question is: Noting that the bond angle of an sp3 hybridized atom is 109.5 and that of an sp2 hybridized atom is 120, do you expect the bond angle between two hybrid orbitals to increase or decrease as the s-character of the hybrids is increased? What exactly does this mean? What is the s-charac...
- Mon Jun 04, 2018 10:33 am
- Forum: Bronsted Acids & Bases
- Topic: J11c
- Replies: 4
- Views: 637
J11c
For the reaction 2HI + CaO -> CaI2 + H2O how do you know which is the acid and which is the base?
- Sun Jun 03, 2018 10:51 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Final
- Replies: 5
- Views: 562
Re: Final
Toolbox 17.1 is also about naming coordination complexes, so I assume that's not needed as well
Re: Chelate
It's a central metal atom attached to ligands in a ring/cyclical structure. The ring structure can only be created with polydentate ligands, that can form coordinate bonds with more than one other atom/molecule. In most cases, the metal atom is bonded to a ligand, which is bonded to another ligand w...
- Thu May 31, 2018 7:58 pm
- Forum: Dipole Moments
- Topic: 4.25d - Lone Pairs
- Replies: 2
- Views: 471
4.25d - Lone Pairs
Do lone pairs have an effect on overall polarity of a molecule? For example the answers say SF4 is polar, even though all the atoms around the central atom are the same and exhibit the same dipole moments that should cancel out. Is it because the lone pairs effects the shape of the structure and pus...
- Sat May 26, 2018 11:56 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Regions of electron density
- Replies: 7
- Views: 708
Re: Regions of electron density
VSPER theory is only concerned with the regions of electron density around the central atom. Lone pairs on non central atoms don't count as regions of electron density
- Sat May 26, 2018 11:50 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Polar Vs. Nonpolar
- Replies: 1
- Views: 2726
Re: Polar Vs. Nonpolar
CFCl3 does exist. I think it is slightly polar. In general, if a central atom has more than 3 atoms around it and the 3 atoms are not all the same, the dipole moments don't completely cancel. In this case, the electronegativity different in C-F is slightly large than that of C-Cl, so there is a resu...
- Sat May 26, 2018 11:44 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Remembering Bond Angles
- Replies: 4
- Views: 605
Remembering Bond Angles
Will we have to memorize bond angles for the final? How much detail will we have to know about them?
- Sun May 20, 2018 11:35 pm
- Forum: Resonance Structures
- Topic: Double bonds
- Replies: 3
- Views: 609
Re: Double bonds
Correct me if I'm wrong, but I don't think that is an explicit rule, I think it just depends on which atoms are bonding to which, and how many electrons (both bonding and lone pair) you need to draw into the Lewis Structure. For example, oxygen tends to form double bonds in both large and small mole...
- Sun May 20, 2018 12:24 pm
- Forum: Ionic & Covalent Bonds
- Topic: 3.59a
- Replies: 2
- Views: 285
3.59a
The question asks to draw the Lewis structure of ClO, which is a radical. How to you know whether the single lone electron goes on the Cl molecule or the O molecule?
- Sun May 20, 2018 11:06 am
- Forum: Ionic & Covalent Bonds
- Topic: 3.25
- Replies: 2
- Views: 347
Re: 3.25
Although in general they have 3+ charges, it also depends on which atom(s) they are bonding with. If an element, like Bi, is bound to a more electronegative element it will have a 3+ positive charge. However, if Bi was the more electronegative atom in a molecule it would likely gain electrons to bec...
- Thu May 17, 2018 4:09 pm
- Forum: Ionic & Covalent Bonds
- Topic: 3.25 e
- Replies: 1
- Views: 325
3.25 e
This question may have an obvious answer, but why does Bismuth have a 3+ charge as opposed to a 3- charge? Arsenic is in the same group as bismuth and has a 3- charge, yet bismuth can bond with 3 F- to create a neutrally charge molecule (BiFe3).
- Sat May 12, 2018 4:24 pm
- Forum: Ionic & Covalent Bonds
- Topic: Nonpolar covalent bonds
- Replies: 2
- Views: 348
Re: Nonpolar covalent bonds
Non-polar covalent bonds are when a bond is formed when electrons are equally shared between two atoms (usually nonmetals belongs to p-block in the periodic table). The difference in electronegativity (tendency to accept bond pair of electrons towards itself) is negligible. So there no separation of...
- Sat May 12, 2018 4:17 pm
- Forum: Ionic & Covalent Bonds
- Topic: radicals [ENDORSED]
- Replies: 9
- Views: 1123
Re: radicals [ENDORSED]
A radicals is a atom/molecule with a single unpaired valence electron. They contain an orbital valence orbital that only has one electron, not two. Radicals are highly reactive.
- Sat May 12, 2018 4:11 pm
- Forum: Ionic & Covalent Bonds
- Topic: Why can't hydrogen be a central atom? [ENDORSED]
- Replies: 6
- Views: 3753
Re: Why can't hydrogen be a central atom? [ENDORSED]
Hydrogen generally can only formed one covalent bond, because of its single valence electron. Therefore, in molecules made up of 3 or more atoms, it would never be in the center because it can only bond with one other atom, as it can only share its singular electron in a covalent bond.
- Wed May 09, 2018 8:27 am
- Forum: Properties of Light
- Topic: Energy vs Intensity
- Replies: 4
- Views: 588
Energy vs Intensity
What's the difference between the energy and the intensity of photons/light?
- Sun May 06, 2018 6:26 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Half filled exception
- Replies: 3
- Views: 1507
Re: Half filled exception
Chromium is an example of the half filled exception. Instead of being Cr = [Ar] 4s^2 3d^4 as expected following the usual rules, it is 4s^1 3d^5. Because the 3d sub shell is more energetically stable if it has one electron in each of its 5 orbitals, that if it were to have only 4.
- Sun May 06, 2018 6:12 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Question 2.41
- Replies: 3
- Views: 377
Re: Question 2.41
B is also false because if the value of l is 0, then the value of ml must be 0 as well
- Sun May 06, 2018 4:52 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 2.37
- Replies: 3
- Views: 519
2.37
Part b) of this question where you have to determine whether the statements are true or false is: Electrons in an s-orbital are more effective than those in other orbitals at shielding other electrons from the nuclear charge because an electron in an s-orbital can penetrate to the nucleus of the ato...
- Mon Apr 30, 2018 1:12 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: 2.29
- Replies: 9
- Views: 1126
2.29
How many electrons can have the following quantum numbers in an atom: (c) n = 2?
The answer says 8 electrons, but wouldn't n = 2 be a p orbital, which has 6 electrons? Where do the other 2 electrons come from?
The answer says 8 electrons, but wouldn't n = 2 be a p orbital, which has 6 electrons? Where do the other 2 electrons come from?
- Sat Apr 28, 2018 12:09 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric effect post-quiz 17-19 [ENDORSED]
- Replies: 7
- Views: 5383
Re: Photoelectric effect post-quiz 17-19 [ENDORSED]
Incident light means the same thing as the photon used to eject the electron in this context, and E = hv is used to convert the energy of the incident light to the frequncy
- Sat Apr 28, 2018 11:59 am
- Forum: Photoelectric Effect
- Topic: What is work function? [ENDORSED]
- Replies: 15
- Views: 5627
Re: What is work function? [ENDORSED]
It is given by the equation energy supplied by a photon - kinetic energy of the ejected electron, or hv - (1/2)mv^2
- Sat Apr 28, 2018 11:49 am
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: 1.43 [ENDORSED]
- Replies: 1
- Views: 213
1.43 [ENDORSED]
"What is the minimum uncertainty in the speed of an electron confined to within a lead atom of diameter 350. pm? Model the atom as a one-dimensional box with a length equal to the diameter of the actual atom." What does the second part of the question mean? What's the significance of havin...
- Thu Apr 19, 2018 7:52 pm
- Forum: Properties of Light
- Topic: Homework Problem 1.5
- Replies: 2
- Views: 281
Re: Homework Problem 1.5
Energy = (planck's constant x speed of light)/wavelength
So the larger the wavelength, the greater the denominator and the lower the energy.
So the larger the wavelength, the greater the denominator and the lower the energy.
- Tue Apr 17, 2018 8:16 pm
- Forum: Properties of Light
- Topic: Question 1.11
- Replies: 2
- Views: 353
Question 1.11
In the spectrum of atomic hydrogen, several lines are generally classified together as belonging to a series (for example, Balmer series, Lyman series, Paschen series), as shown in Figs. 1.10 and 2.1. What is common to the lines within a series that makes grouping them together logical? The answers ...
- Tue Apr 17, 2018 7:15 pm
- Forum: Properties of Light
- Topic: HW 1.3 [ENDORSED]
- Replies: 12
- Views: 1618
Re: HW 1.3 [ENDORSED]
Also, what does the electric field in this context refer to?