CHEMISTRY COMMUNITY

Neha Divi 1K

Can someone outline the steps for determining the molecular and VSEPR shape? Like, how one should go about solving a problem when asked on an exam.

Neha Divi 1K

Hybridization is the concept of mixing atomic orbitals into new hybrid orbitals suitable for the pairing of electrons to form chemical bonds in the valence bond theory. The hybrid orbitals allow one to explain the molecular geometry and atomic bonding properties.

Neha Divi 1K

Adding on to what other students said, an oxoacid is an acid that contains oxygen, one other element, has at least one hydrogen bonded to the oxygen, and forms an ion by the loss of one or more protons. As stated above, acid strength increases when the central atom stays the same and as the number o...

Neha Divi 1K

To add on, a sigma bond is a covalent bond resulting from the formation of a molecular orbital by the end-to-end overlap of atomic orbitals. These overlaps can occur between s-s, p-p, s-p

Neha Divi 1K

To add on to what others said, VSEPR is used as a model in chemistry to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms.

Neha Divi 1K

A pi bond is a covalent bond that results from the formation of a molecular orbital by side-to-side overlap of atomic orbitals along a plane perpendicular to a line. A double bond actually has one sigma and one pi bond.

Neha Divi 1K

I also was looking up more information and I found that bond angles are affected the three factors: state of hybridization of central atom, lone pair repulsion, and electronegativity. Lone pair of electrons at the central atom always try to repel the shared pair of electrons, thus, bonds are slightl...

Neha Divi 1K

In addition, we learned in class on Friday that a polar molecule must have polar bonds with dipoles that do not cancel and that a non polar molecule must have zero electric dipole moment which is possible if it contains non polar bonds or polar bonds with dipoles that cancel.

Neha Divi 1K

For determining whether a molecule is polar or not, you need to look at the dipole moments. If the dipole moments are going in opposite directions and cancel each other out then it is non polar. If the dipoles do not cancel it is a polar molecule. Dipole moments occur when there is a separation in c...

Neha Divi 1K

Formal charge can be calculated by looking at the number of electrons an atom wants and then subtracting each electron in lone pairs surrounding the atom and any electrons bonded (1 for each line in the lewis structure). In addition, the formula Dr. Lavelle stated in class was FC=V-(L+(S/2)).

Neha Divi 1K

The lines represent a bond between two atoms. Drawing a line on atom to represent a lone pair would not represent what the structure actually looks like since there is no bond. So when drawing lone pairs, just use the dots.

Neha Divi 1K

I think you look at the formal charge like the student above stated, but also you can look at the number of electrons total and make sure whether you use a double bond and lone pair versus a triple bond that it still includes all the electrons as well as the formal charge.

Neha Divi 1K

The formal charge is the difference between the number of valence electrons "belonging" to the bonded atom and those in the full valence shell. And, no the formal charge is not always 0, but that is when it has the lowest energy.

Neha Divi 1K

As the person above stated, calcium has two valence electrons (from the 4s orbital) that is must lose to have a complete octet. When it does this, it will behave like the atom Argon.

Neha Divi 1K

Yup! I think the oxidation numbers are essentially a way to keep track of how many electrons an atom has, thus, depending on the other atoms involved.

Neha Divi 1K

Another way to think of Hund's Rule is thinking about how people sit on a school bus. People are more likely to sit in a seat by themselves before sitting next to someone else. Electrons in orbitals act the same way. There will not be paired electrons until each one occupies one spot in an orbital.

Neha Divi 1K

I agree with what was stated above. I think it follows the exceptions discussed in class about how a full 3d orbital, d^10, has a lower energy than the 4s orbital and how the electrons occupy the lower energy state first before filling the 4s orbital in this case.

Neha Divi 1K

Zeff is notation for the effective nuclear charge. In the textbook, it discusses how electrons are attracted to the nucleus, but also repelled by other electrons present. As a result, it is less tightly bound to the nucleus than it would be if other electrons were absent. Thus, each electron is shie...

Neha Divi 1K

I agree with the student above, additionally, the nodal plane is such a plane that does no intersect the associated orbital at any point, therefore, a low probability of finding an electron there.

Neha Divi 1K

In addition to what everyone said, think about the context of the problem. You typically use the kinetic energy equation for the photoelectric effect and a situation describing it whereas the DeBroglie equation relates a moving particle's wavelength to its momentum, mass*velocity.

Neha Divi 1K

By using E=hv which is the quantization of electromagnetic radiation and the speed of light equation where c=lambda*v you are finding the photon energy and since you know the total energy for 2 seconds which is 64J, by dividing the total energy generated by the lamp and the energy per photon you get...

Neha Divi 1K

Additionally, using the empirical formula and knowing the molar mass allows you to find the molecular formula by dividing the molar mass by the mass of the empirical compound to find the actual number of atoms in the molecular formula compared to the ratio.

Neha Divi 1K

1.25 Sodium vapor lamps, used for public lighting, emit yellow light of wavelength 589 nm. How much energy is emitted by (b) 5.00 mg of sodium atoms emitting light at this wavelength; Hi, I was slightly confused on following the steps for part b. I was wondering if someone could explain them more th...

Neha Divi 1K

Personally, I like to look for the element that is present the least on both sides as a starting point. From there I try to start with the elements that have smaller quantities present on both sides of the reaction. In addition, like the example Dr. Lavelle used in class I will utilize fractions and...

Neha Divi 1K

To add on, the photoelectric effect is the idea that there is an ejection of electrons from a metal when its surface is exposed to ultraviolet radiation. Furthermore, no electrons are ejected unless the radiation has a frequency above a certain threshold that is characteristic of a metal.

Neha Divi 1K

The question asks you to arrange the following electromagnetic radiation in order of increasing energy. After you find the frequency, you use that value and multiply it by plancks constant not divide to find the value of energy (E=hv). You then rank the radiations for increasing energy. You can also...

Neha Divi 1K

Additionally, blackbody radiation is a theoretical concept in quantum mechanics in which a material or substance completely absorbs all frequencies of light and therefore reflects no radiation and appears black. An example would be a star. Most of the light directed at the star is absorbed, capable ...

Neha Divi 1K

The question from the textbook says: Arrange the following types of photons of electromagnetic radiation in order of increasing energy: -rays, visible light, ultraviolet radiation, microwaves, x-rays. Like the student above, said you know that the speed of light, c, equals lambda*v(the frequency), t...

Neha Divi 1K

I agree with what everyone else said. In addition, I think the answer was trying to show the value without scientific notation and in terms that would help you understand the scope of the problem and compare that to the answer and its units.

Neha Divi 1K

The colors of photons of the electromagnetic radiation refer to visible light and the different colors that you see. Visible light ranges from 700nm (red light) to 400 nm (violet light) which has a spectrum of colors within that range. The wavelengths represent the different regions of the spectrum ...

Neha Divi 1K

In addition, if you focus on the valence electrons, there would be 8 electrons for C2- while there would only be 4 electrons for C2+. Therefore, the 8 electrons would fill up both outer orbitals, the s and p orbitals, while for C2- it would only fill up the 1s orbital and have 2 electrons in the 2s ...

CHEMISTRY COMMUNITY

Search found 31 matches

Outlining Steps for Determining Shape

Re: basics of hybridization

Re: Oxoacids

Re: σ bonds

Re: VSEPR confusion

Re: Double bond

Re: Bond Angles

Re: Polar & Nonpolar

Re: Polar Bonds versus non polar bonds

Re: formal charge

Re: FORMAL CHARGE

Re: Double Bond vs Triple Bond

Re: Formal charges and full valence shells

Re: Octet fule in forming compounds

Re: Oxidation Number & Bonds

Re: Hund's Rule [ENDORSED]

Re: 2.43

Re: Zeff

Re: Nodal Planes [ENDORSED]

Re: When to use DeBroglie or Ek equation

Re: calculating the number of photons

Re: empirical vs molecular

Homework 1.25b

Re: Balancing Equation

Re: Threshold Energy [ENDORSED]

Re: Example 1.5 in the textbook [ENDORSED]

Re: What is Significant about Black Body Radiation? [ENDORSED]

Re: HW ch1 question 5

Re: HW 1.7 (using nm vs pm)

Re: HW 1.5 [ENDORSED]

Re: C2+ C2-