CHEMISTRY COMMUNITY

Taizha 1C

Acidic rain forms from sulfur dioxide and nitrogen are released in to the air (as from coal power plants) and interact with water or oxygen.

Taizha 1C

For part A, use the equation m1v1=m2v2. So 1.50*v1=(.550m)(210mL), v1=77mL.

For part B, use pH+pOH=14-(-log[OH-]), so pH=14.04.

Taizha 1C

In the UA session, she was saying that it's like "spotting the difference" between them. So you would compare the electronegativity of the right side of the 4 since the left are similar in 1, 2, and 3.

Taizha 1C

Hi, Why is the answer for 4.21d a trigonal pyramidal with 107 degrees? The question asked for the lewis structure and angle of N2H4. I was wondering why the bond angle wouldn't be the same as part a in the same question for C2H4 that has a bond angle of 120 degrees. Also, why couldn't a double or tr...

Taizha 1C

Oh no, sorry I mean just one midterm.

Taizha 1C

Amphoteric has both acid and basic characters and properties. Amphiprotic acts as a proton donor or acceptor. An example of this would be water (H2O). It could become H3O or either -OH. To be considered amphiprotic, does it have to act as a proton donor and acceptor, or only one of the two? Yes, I ...

Taizha 1C

Amphoteric has both acid and basic characters and properties. Amphiprotic acts as a proton donor or acceptor. An example of this would be water (H2O). It could become H3O or either -OH. It would also be helpful to know polyprotic which has more than one proton to donate ( if it is an acid) or accep...

Taizha 1C

Amphoteric has both acid and basic characters and properties. Amphiprotic acts as a proton donor or acceptor. An example of this would be water (H2O). It could become H3O or either -OH.

Taizha 1C

Hi, Does anyone have access to past final exams, tests, or midterms from past 14a course readers? If so, does anyone mind emailing me? ak9ee@g.ucla.edu

Taizha 1C

A TA told me that it would be similar to the set up from midterm 1 and 2. So 8 questions total. 4 questions may be from either midterm 1 or 2, and the other 4 will be new material. But each question will have multiple parts. But I'm not sure how accurate this is.

Taizha 1C

Alejandro Salazar 1D wrote:I would recommend memorizing the 7 common strong acids, which are HCI, HBr, HI, HNO3, HCIO3, HCIO4, H2SO4

Are those acids already ranked from strongest to weakest? For example, HCl > HBr > HI ......?

Taizha 1C

Thank you Dr. Lavelle!

As a first year at UCLA, you made me feel comfortable taking 14A this quarter with no prior chemistry background from high school!

Taizha 1C

How would i determine the differences in strengths of acids? or how would i rank the acids? Would i determine the strength based on which is most acidic and which is the most electronegative?

...or does anyone have any recommendations to do this?

Taizha 1C

Are metal oxides bases and nonmetal oxides acids?

Taizha 1C

What is an example of how we may be given a test question for sigma and pi bonds?

Taizha 1C

Okay, thank you! I believe I understand how to determine the difference now.

Taizha 1C

Hi, I read that molecules with the same VSEPR formula have the same shape, but differ in bond angle. How would I determine the difference between the bond angles in different molecules with the same shape and VSEPR formula? Also how would I be able to recognize the exceptions to this? In the book it...

Taizha 1C

If we were to encounter a molecule with a single lone pair electron on the central atom, how would we began to determine the shape?

Taizha 1C

For the length of bond the order is: triple < double < single.

Taizha 1C

@Ashley, because single bonds and multiple bonds are treated as equivalent in the VSEPR model, it doesn't matter which of the Lewis Structures contributing to a resonance structure we consider.

Taizha 1C

I think they're both correct, but they're usually written as equally distributed.

Taizha 1C

For more on determining stable lewis structures, refer to example 3.6 in the text book. It includes an example, and indicates the equation with all steps.

Taizha 1C

For test 3, should we identify if a covalent bond is polar or non polar?

Taizha 1C

Does anyone know if we need to know aufbau, hund, and pauli principles?

Taizha 1C

the answer is 4f^14 because you need to include the configuration for the f-block, so not including La, there would be 14 e- total.

Taizha 1C

What type of midterm questions/practice problems are possible for s, p, d, f?

Taizha 1C

For the upcoming midterm, do we need to be familiar with any other series besides balmer and lyman series?

Taizha 1C

Will there be a guide or list of chem topics that we need to focus on for the upcoming midterm?

Taizha 1C

Has anyone found any other resources outside of class that is useful for preparing for the test? Like any practice exam/test problems?

Taizha 1C

What is a good way to determine when to used avogadro's #?

Taizha 1C

So we still need to memorize the units of the equations?

Taizha 1C

Do we need to memorize the speed of light in different conditions for the exam?

Taizha 1C

I have not taken Chemistry since high school and the first test for outline 1 was difficult. Is there any practice problems that are more similar to test questions or are more difficult than the weekly homework problems?

Taizha 1C

Does anybody have a groupme link for the study group?

Taizha 1C

If we have our discussion towards to beginning of the week, are we able to answer questions from outline 1 instead of outline 2? I have discussion on Tuesday and I feel like we haven't went over new materials on outline 2.

Taizha 1C

According to lecture precision indicates how close measurements are to one another while accuracy is the accuracy to the true value.

CHEMISTRY COMMUNITY

Search found 36 matches

Re: Acid Rain

Re: French Toast #27a

Re: strong/weak acids (from review worksheet)

hw 4.21d

Re: Final [ENDORSED]

Re: Amphoteric and amphiprotic

Re: Amphoteric and amphiprotic

Re: Amphoteric and amphiprotic

Past Final Exams

Re: Final [ENDORSED]

Re: Determining Acid Strength

Re: Saying Thank You to Dr. Lavelle

Determining Acid Strength

metal oxides

Re: Difference between Bonds [ENDORSED]

Re: VSEPR shape and bond angles

VSEPR shape and bond angles

Molecules with lone pairs

Re: Bond Strength

Re: VSEPR and Lewis

Re: Different ways to write the lewis structure?

Re: Stable Lewis structures

Re: Test 3

Re: Midterm Topics [ENDORSED]

Re: homework 2.43 part e [ENDORSED]

Re: s, p, d, f

Re: Balmer and Lyman Series

Re: Study Guide for Midterm? [ENDORSED]

Re: Reading the textbook

Re: Avogadro #

Re: Memorizing formulas test 2

Re: Speed of light constant

Re: Rusty on High School Chem [ENDORSED]

Re: Study Group

Re: Homework? [ENDORSED]

Re: Accuracy vs Precision