CHEMISTRY COMMUNITY

Vivian Gonzalez 1A

Bond angles do not have to be accurate for lewis structure and if I remember correctly we will not be asked to draw the shapes for VSEPR. We just need to know the names of the shapes and the bond angles

Vivian Gonzalez 1A

Can anyone explain in more detail what a conjugate base and acid are and how to determine whether a molecule is a conjugate base or acid?

Vivian Gonzalez 1A

I am also confused as to how we know to include chloride in the acids equation and sodium in the base equation.

Vivian Gonzalez 1A

What do we need to know about pi and sigma bonds for the final?

Vivian Gonzalez 1A

How do we know when to apply hybridization?

Vivian Gonzalez 1A

Based on the lewis structure there are 2 regions of electron density, therefore, the molecule has a linear shape with 180 degree angles.

Vivian Gonzalez 1A

Also in discussion my TA mentioned that when they ask for the geometry of the molecule, they want you to include the lone pairs, but if they ask for the molecular structure, they want you to not include the lone pairs and just describe what would be observed. So just beware that questions could ask...

Vivian Gonzalez 1A

In lecture, the polar molecule we were using as an example was cis-dichloroethene. The cis just means that the two chlorine atoms were on the same side giving the molecule its polarity. On the other hand, there was also trans-dichloroethene where the chlorine atoms were on opposite sides and so the ...

Vivian Gonzalez 1A

This is called lone pair repulsion and a lone pair of electron at the central atom always tries to repel bonded pair of electrons. This causes bonds to be displaced resulting in a decrease of bond angle.

Vivian Gonzalez 1A

A dipole is a separation of opposite electrical charges. The larger the difference in electronegativity, the greater the dipole moment.

Vivian Gonzalez 1A

I also had a similar question and Alicia your response really cleared things up on covalent character. Thank you

Vivian Gonzalez 1A

I am also confused as to what the term covalent character means or is referring to. Can someone please explain?

Vivian Gonzalez 1A

I agree with what the others said, but I think it is easier to think of size in terms of the definitions of cation and anion. Anions gain electrons so they will grow in size, while cations lose electrons so their size will decrease.

Vivian Gonzalez 1A

From what I understand the line represents a shared electron, however, my question is how do we know whether a bond is ionic or covalent?

Vivian Gonzalez 1A

I remember the difference between a cation and anion by seeing that anion starts with an "a" just like the work add. So for anions you add electrons.

Vivian Gonzalez 1A

I see. So the f block lies in between the 6s-7s and 5d/6d rows?

Vivian Gonzalez 1A

The question asks what is the ground-state electron configuration expected for each of the following elements: (e) tungsten?
The answer is: [Xe] 4f^14 5d^4 6s^2
I understand where the 5d^4 and 6s^2 came from, however, I'm still confused on how to get 4f^14. Can someone please explain?

Vivian Gonzalez 1A

It wouldn't work to use lambda=hc/E at first because we don't know the energy of the photon. In order to use that equation we need to solve for energy using the equation: Energy of photon=(threshold/work function)+1/2 m*v^2

Vivian Gonzalez 1A

The Balmer series uses visible light.

Vivian Gonzalez 1A

The only reason I can think of is since the 3d state is higher in energy than the 4s state, the 4s state would fill up faster because it would take less energy.

Vivian Gonzalez 1A

Electrons aren't fixed to a certain position, but are orbitals? Is an orbital just a reference to a specific region?

Vivian Gonzalez 1A

It is the same formula. Just as wavelength is sometimes noted as lambda, frequency is noted as v.

Vivian Gonzalez 1A

Basically, long wavelengths have low frequencies while short wavelengths have high frequencies.

Vivian Gonzalez 1A

The photoelectric effect measures the energy needed to remove electrons from different metals. In the photoelectric experiment, light sources with long wavelengths cannot eject e-, however, light sources with short wavelengths (high frequencies) can eject e-.

Vivian Gonzalez 1A

Planck's constant came about from his studies of black-body radiation. He proposed the exchange of energy between matter and radiation occurs in quanta of energy. You can read more about this in the textbook on page 9-11.

Vivian Gonzalez 1A

A photon is characterized by either a wavelength(lambda) or equivalently an energy(E). The energy of each photon is inversely related to the wavelength of the associated EM wave.

Vivian Gonzalez 1A

For homework, choose from the problems listed for The Quantum World chapter 1

Vivian Gonzalez 1A

Threshold energy is the amount of energy needed to eject an electron from a metal.

Vivian Gonzalez 1A

I agree with the others. I think reagent and reactant can be used interchangeably. A reactant participates and is consumed in a chemical reaction. A reagent is sometimes used in the place of a reactant but may not be consumed in a reaction.

Vivian Gonzalez 1A

An extensive property is a property that depends on the amount of matter in a sample. Mass and volume are examples of extensive properties. An intensive property does not depend on the system size or the amount of material in the system. Color, temperature, density and solubility are examples of int...

CHEMISTRY COMMUNITY

Search found 30 matches

Re: Drawing Lewis Structures on the Final Exam

Re: Conjugate Acids/Bases

Re: As2O3

Re: pi bond and sigma bond

Re: basics of hybridization

Re: homework problem 4.17 [ENDORSED]

Re: List of the different shapes

Re: cis and trans

Re: Bond angle

Re: Meaning of a dipole

Re: Polarization

Re: ionic character

Re: cations vs anions

Re: Meaning of chemical bond

Re: cation vs anion

Re: homework 2.43 part e [ENDORSED]

homework 2.43 part e [ENDORSED]

Re: In class problem 5/4

Re: Balmer Series

Re: Why does 4s fill up before 3d?

Re: understanding orbitals [ENDORSED]

Re: E=hv vs E=hf [ENDORSED]

Re: frequency and wavelength [ENDORSED]

Re: Photoelectric Effect

Re: Planck's constant [ENDORSED]

Re: HW 1.5 [ENDORSED]

Re: Homework 3

Re: Threshold Energy [ENDORSED]

Re: Reagent vs. Reactant [ENDORSED]

Re: Extensive vs. Intensive Properties?