Search found 31 matches

by gillianozawa4I
Fri Dec 07, 2018 11:43 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Polydentates
Replies: 1
Views: 41

Re: Polydentates

You can tell if a ligand is polydentate by determining the number of places the ligand is binding to the central atom (transition metal). For instance, if a ligand is acting as a tetradentate, ligand is bound to the central atom in four places. Hope this helps!
by gillianozawa4I
Fri Dec 07, 2018 2:21 am
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Boiling Point
Replies: 6
Views: 197

Re: Boiling Point

H2Se has the higher boiling point because it has a larger mass and more electrons. Because Se has more electrons, it is more polarizable and therefore has stronger London Dispersion Forces than H2S. This causes it to have a higher boiling point. Hope this helps!
by gillianozawa4I
Fri Dec 07, 2018 2:18 am
Forum: Bronsted Acids & Bases
Topic: Exceptions: HSO4- and H2PO4-
Replies: 4
Views: 77

Re: Exceptions: HSO4- and H2PO4-

HSO4- and H2PO4- can act like acids because they have a free proton they are able to donate in a basic environment. Hope this helps!
by gillianozawa4I
Fri Dec 07, 2018 2:11 am
Forum: Conjugate Acids & Bases
Topic: Charges when naming it acid or base
Replies: 1
Views: 83

Re: Charges when naming it acid or base

H2PO4- is an acid because it donates a proton to water (which in this case acts as a base because it is a proton acceptor) to form HPO42-. Water can act as both an acid or a base because it can accept protons (to form H3O+) or donate protons (to form OH-). Hope this helps!
by gillianozawa4I
Thu Nov 29, 2018 11:47 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: polar or not polar
Replies: 4
Views: 116

Re: polar or not polar

In a molecule with one central atom, (a majority of the time ) if the surrounding atoms are different, the molecule is polar. This is because the surrounding atoms have different electronegativity values that do not cancel out. However, I think it's best to draw out the Lewis structure to determine ...
by gillianozawa4I
Thu Nov 29, 2018 11:41 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone pairs
Replies: 3
Views: 92

Re: Lone pairs

Lone pairs also have a larger electron cloud and occupy more space than a bond. As a result, the lone pair pushes the bonds away from it, lessening the bond angle slightly. Hope this helps!
by gillianozawa4I
Thu Nov 29, 2018 11:32 pm
Forum: Hybridization
Topic: Hybridization Notation
Replies: 10
Views: 182

Re: Hybridization Notation

Either notation is correct.
by gillianozawa4I
Fri Nov 23, 2018 2:07 pm
Forum: Dipole Moments
Topic: Relationship between atomic size and attractive forces
Replies: 2
Views: 76

Re: Relationship between atomic size and attractive forces

In fluorine, electrons are tightly held to the nuclei, so the electrons are not easily distorted. As a result, the LDF's are weak. In iodine, electrons are further from the nuclei so they are easier to distort, so LDF's become stronger. Therefore, iodine is a solid while fluorine is a gas at room te...
by gillianozawa4I
Fri Nov 23, 2018 2:01 pm
Forum: Sigma & Pi Bonds
Topic: Double Bonds
Replies: 9
Views: 306

Re: Double Bonds

Yes, double bonds consist of one sigma and one pi bond. The pi bond is the "second" bond in the double bond.
by gillianozawa4I
Fri Nov 23, 2018 1:50 pm
Forum: Hybridization
Topic: stating the hybridization of an atom
Replies: 3
Views: 71

Re: stating the hybridization of an atom

Although I'm not completely sure, I think you would have to state the "2" because the number in front of "sp" makes a difference in hybridization.
by gillianozawa4I
Wed Nov 14, 2018 11:54 am
Forum: Dipole Moments
Topic: Dipole Moments [ENDORSED]
Replies: 10
Views: 206

Re: Dipole Moments [ENDORSED]

A dipole-dipole interaction occurs when two polar molecules interact. The partially positive side of one molecule is attracted to the negative side of the other molecule. This is different from a dipole-induced dipole interaction because in a dipole-induced dipole interaction, a polar molecule induc...
by gillianozawa4I
Wed Nov 14, 2018 11:42 am
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR
Replies: 3
Views: 76

Re: VSEPR

The VSEPR (valence shell electron pair repulsion) model helps predict the geometry of a molecule based on the the molecule's Lewis structure and its regions of high electron density. Since these regions repel one another, the shape of the molecule is affected. This is why the geometry changes when t...
by gillianozawa4I
Wed Nov 14, 2018 11:35 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 3
Views: 111

Re: Bond Angles

I think we do have to memorize the bond angles, but they can also be calculated once you have the Lewis structure of the molecule.
by gillianozawa4I
Fri Nov 09, 2018 10:51 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Tetrahedral molecules
Replies: 4
Views: 74

Re: Tetrahedral molecules

Yes, tetrahedral molecules all have 109.5 degree angles because they consist of a central atom surrounded by four surrounding atoms, without any lone pairs on the central atom. Lone pairs on the central atom cause the angles to change due to their negative charge. Hope this helps!
by gillianozawa4I
Fri Nov 09, 2018 10:46 am
Forum: Dipole Moments
Topic: Dipole induced dipole
Replies: 3
Views: 73

Re: Dipole induced dipole

In a dipole-induced-dipole interaction, a polar atom can cause electron distribution on a neutral atom to become distorted. This distortion causes the neutral atom to become polar. For instance, in the molecule consisting of HCl and N2, the electrons in Cl repel the electrons on N, inducing a dipole...
by gillianozawa4I
Fri Nov 09, 2018 10:29 am
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: ionic vs. covalent character
Replies: 3
Views: 99

Re: ionic vs. covalent character

High ionic character means that there is a large difference in electronegativity between the two atoms. The ionic character of a covalent bond means that electrons are not attracted equally between the two atoms. High covalent character in an ionic bond means that electrons are partially shared and ...
by gillianozawa4I
Wed Oct 31, 2018 1:02 am
Forum: Lewis Structures
Topic: Stable Lewis Structures
Replies: 4
Views: 77

Re: Stable Lewis Structures

I would test out all the different combinations of double bonds in the lewis structure (that match the number of electrons) and calculate the formal charge for each one. The formal charge closest to zero is the most stable.
by gillianozawa4I
Wed Oct 31, 2018 12:33 am
Forum: Electronegativity
Topic: Electronegativity vs Electron Affinity [ENDORSED]
Replies: 1
Views: 98

Re: Electronegativity vs Electron Affinity [ENDORSED]

Electron affinity measures the amount of energy released when an electron is added to that element. Electronegativity, on the other hand, measures the ability for an element to attract electrons in a covalent bond (a bond where electrons are shared, rather than transferred). If electronegativity is ...
by gillianozawa4I
Wed Oct 31, 2018 12:19 am
Forum: Lewis Structures
Topic: Valence Electrons
Replies: 7
Views: 101

Re: Valence Electrons

PCl5 has five bonds, meaning there are 10 valence electrons. Therefore, PCl5 has an expanded octet. Since P is in Period 3, it is allowed to have an expanded octet. Hope this helps!
by gillianozawa4I
Thu Oct 25, 2018 5:20 pm
Forum: Quantum Numbers and The H-Atom
Topic: Degeneracy
Replies: 4
Views: 134

Re: Degeneracy

All of the orbitals in the shell of a hydrogen atom are degenerate. Orbitals with the same n but different values of l is true only for the hydrogen atom and one-electron ions.
by gillianozawa4I
Thu Oct 25, 2018 4:57 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Losing electrons to form cations
Replies: 2
Views: 98

Re: Losing electrons to form cations

Electrons in the outermost energy level are the easiest to remove, so they will be removed first. This is because the pull from the positive charge in the nucleus is the weakest at the outermost energy levels (due to shielding). Hope this helps!
by gillianozawa4I
Thu Oct 25, 2018 4:55 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Why is there a negative?
Replies: 4
Views: 159

Re: Why is there a negative?

I think there is a negative sign in the equation to show that energy is emitted (because the electron goes from a higher to a lower energy state). If energy was absorbed, the answer would end up being positive. Hope this helps!
by gillianozawa4I
Wed Oct 17, 2018 12:00 am
Forum: DeBroglie Equation
Topic: Homework Problem 1b.15
Replies: 2
Views: 84

Re: Homework Problem 1b.15

Yes, you would plug it into de Broglie's equation. Momentum is found by multiplying mass of the electron by the velocity, and mass of the electron is given on the formula sheet. The equation gives the velocity, so you would just have to multiply these two values to get momentum. Hope this helps!
by gillianozawa4I
Tue Oct 16, 2018 11:56 pm
Forum: Properties of Light
Topic: calculating wavelength
Replies: 10
Views: 348

Re: calculating wavelength

I think that it depends on the equation given. One equation requires frequency to solve for wavelength, while the other requires momentum (mass*velocity) to solve. I would choose the equation keeping these values in mind. Hope this helps!
by gillianozawa4I
Tue Oct 16, 2018 11:53 pm
Forum: Properties of Electrons
Topic: electrons
Replies: 3
Views: 88

Re: electrons

Electrons have wavelike properties because they are capable of diffraction. When electrons pass through a crystal/prism, they create a pattern of high and low intensities. When the peaks and troughs of waves traveling along a path interfere with waves along another path, the result is a diffraction ...
by gillianozawa4I
Thu Oct 11, 2018 1:02 am
Forum: Einstein Equation
Topic: 7th 1B.15 When do you use E = hv or Ek = 1/2m v^2?
Replies: 4
Views: 130

Re: 7th 1B.15 When do you use E = hv or Ek = 1/2m v^2?

I agree with this. When given velocity, use Ek = 1/2 mv^2. It's also be confusing because "v" in E=hv is frequency, while v in Ek = 1/2mv^2 is velocity. E=hv is the energy brought by the photon, while Ek is E=hv minus the work function (threshold value).
by gillianozawa4I
Thu Oct 11, 2018 12:43 am
Forum: Photoelectric Effect
Topic: Significance of Photoelectric Effect
Replies: 3
Views: 58

Re: Significance of Photoelectric Effect

I think that the photoelectric effect is significant because of the "wave-particle duality." Through the photoelectric effect, one can observe that photons act like particles (when a metal surface is exposed to UV radiation, electrons are ejected if the radiation surpasses the threshold va...
by gillianozawa4I
Thu Oct 11, 2018 12:22 am
Forum: Empirical & Molecular Formulas
Topic: Question M19: Empirical and Molecular formula of caffeine [ENDORSED]
Replies: 4
Views: 166

Re: Question M19: Empirical and Molecular formula of caffeine [ENDORSED]

I found the answer in a similar way. It is easiest to find the mass of elements that appear the least number of times in the equation first. You can isolate the carbon from CO2 by multiplying 1 mol of C/1 mol of CO2, because there is 1 carbon per 1 CO2 (1:1 ratio). It is definitely easiest to save f...
by gillianozawa4I
Wed Oct 03, 2018 12:29 am
Forum: Molarity, Solutions, Dilutions
Topic: Module question
Replies: 4
Views: 116

Re: Module question

The way I did the problem was to first convert 55.1 g of KCl to moles. The molar mass of KCl is 74.6 g/mol, so 55.1/74.55 is 0.739. Since the number of moles remain the same in a dilution problem, you need to just divide the number of moles by the number of liters, which is .125 L. 0.739/0.125 = 5.9...
by gillianozawa4I
Wed Oct 03, 2018 12:12 am
Forum: Significant Figures
Topic: F.15
Replies: 4
Views: 83

Re: F.15

When multiplying and dividing values with different numbers of sig figs, round down. This is because the answer is no more precise than the value with the least number of sig figs.
by gillianozawa4I
Wed Oct 03, 2018 12:07 am
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Excercise F13
Replies: 2
Views: 63

Re: Excercise F13

From my understanding, the solutions manual combined many of the steps we learned in lecture, but it still solved it in a similar way. First, they found moles of both P and Cl by dividing 4.14 g P (given) by its molar mass (30.97 g/mol) and by dividing 23.66 g Cl (total mass - mass of P) by its mola...

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