CHEMISTRY COMMUNITY

Rachel McMillan 3A

On Quiz #3, I was wondering how the following compound would be named (picture attached):
Thank you!

Rachel McMillan 3A

chapter 15- Chemical Kinetics

Rachel McMillan 3A

In problems 25c I encountered a problem In 23 part c, the question asks us to determine the rate constant for the first order reaction for the equation 2A->B+C given that [A0]=.153, and that after 115 sec the concentration of B rises to .034 M. I tried to calculate the concentration of A by multiply...

Rachel McMillan 3A

I was going through problems in Ch8, and I am confused as to when I should use q=nCdeltaT and q=CdeltaT? Could somebody please clarify this? Thank you :)

Rachel McMillan 3A

For number 5 on the first Quiz #3 prep, I understand why 1 is assigned to iodo (because it is the bigger atom so it has priority), but why is it 3-bromo-1-iodohexane instead of 1-iodo-3-bromohexane?

Rachel McMillan 3A

For the lewis structure 2-Methyl-1, 3-butadiene, what does the 1 after methyl signify? This is one of the examples of an alkene on page 3 of our Organic Molecules textbook. Thank you!

Rachel McMillan 3A

In the Quiz 2 prep that we are turning in, I'm having trouble figuring out how many significant figures to use for #4. When a fraction is involved such as 1/32, do we use two or three significant figures in the answer, or do we ignore the fraction entirely and simply use the other numbers in the pro...

Rachel McMillan 3A

For #8 part b we were asked what the effect of the precipitation of CdS was on cell potential when sodium sulfide is added to the Cd+2 half-cell. I honestly have no idea what the effect of this would be. Can anybody please help? Thanks :)

Rachel McMillan 3A

On number four of our quiz, the problem asks what the work is when an ideal gas expands from 2.0 L to 6.0 L. The initial internal pressure is 1.00 atm. I used w=-P*deltaV, which was incorrect. Which equation should I use? Thank you :)

Rachel McMillan 3A

On our first quiz, we were asked to calculate the mean bond enthalpy of the H-F bond. Delta H was calculated to be -539 kJ, and the problem states that Hydrogen gas reacts explosively with fluorine gas. Because a bond was formed between Fluorine and Hydrogen, does -539 kJ become +539 kJ?

Rachel McMillan 3A

In the 5th edition of our textbook, #37 asks for the value of Q and for a balanced equation. Here is the information given for part a: (a) Pt(s)|Sn4(aq), Sn2(aq)||Pb4(aq), Pb2(aq)|C(gr), E 1.33 V. I thought that I would use Nernst equation but I don't have the concentrations of the ions. What ...

Rachel McMillan 3A

In the 5th edition of our textbook, example 13.3 asks what the reaction Gibbs free energy is when "the potential of the Daniell cell for certain concentrations of copper and zinc ions is 1.04 V." The example then states that, "From the chemical equation for the cell reaction (reaction...

Rachel McMillan 3A

In number 11 of the Winter 2014 Quiz 1 prep, the question asks, "A system undergoes a two-step process. In step 1, it expands adiabatically from 1.00 L to 2.56 L at 1.00 atm (external pressure). In step 2, it releases 73 J of heat at 1.00 atm as it returns to the original internal energy. Find ...

Rachel McMillan 3A

On homework question 8.27 the question asks for us to calculate the work for two processes that began with a gas sample at 305 K, a pressure of 1.79 atm, and a volume of 4.29. In part a, we are asked to calculate the work for an irreversible expansion- I am able to do this part. However, in part b, ...

Rachel McMillan 3A

In Chapter 8.11, one of the first self-tests asks for the enthalpy of vaporization of Benzene at its boiling point. The problem states that "a sample of benzene was heated to 80 degrees Celsius, its normal boiling point. The heating was continued until 15.4 kJ had been supplied; as a result, 39...

Rachel McMillan 3A

I'm having difficulty understanding the significance of reversible and irreversible reactions. What is the difference between the two and why are they important? Thank you :)

Rachel McMillan 3A

Note: Posting this now that I know how to convert files to .mov format. This video was originally posted over a week ago by my partners.

Chem 14A video %3B%29.mov [ 406.27 MiB | Viewed 3048 times ]

Rachel McMillan 3A

This is the mov version of the file

Chem 14A Problem 11.115.mov [ 108.67 MiB | Viewed 3345 times ]

Rachel McMillan 3A

Participant #2 of this video. Enjoy!

Rachel McMillan 3A

In homework problem #23 in the 5th edition of the Chemistry Textbook, the problem asks if the products or reactants will be favored (or if they will be at equilibrium) when Q=1.0 for the equation N2(g)+O2(g) -> 2NO(g). The back of the textbook indicates that the reactants will be favored. I think th...

Rachel McMillan 3A

#29 in the 5th edition of our Chemistry textbook asks us to write out the formula for the coordination compound sodium bisoxalato(diaqua) ferrate (III). What does bis mean and how does it change how the formula is written out?

Rachel McMillan 3A

I am having difficulty understanding the concept of Q, the reaction Quotient. What is Q and why is it significant when we consider K?

Rachel McMillan 3A

In the 5th edition of the textbook in Chapter 3.2, Rule 4 indicates "Strengths of repulsions are in the order lone pair- lone pair > lone pair- atom> atom-atom." I am having difficulty understanding what this means. What do "lone pair- lone pair," "lone pair- atom," and...

Rachel McMillan 3A

In my discussion today, we discussed resonance structures. My TA asked if we had PF5, and removed an electron, which area would we remove the electron from: the poles or the equatorial region? My TA said it would be the equatorial region, but I am unsure as to why. Could somebody please explain this...

Rachel McMillan 3A

In problem #9 of the Self-quizzes, the mass percentages of C,H, and O add to 99.89. After dividing the mass percentages by their respective molar masses and then dividing by the smallest value, I found that Hydrogen's value to be 2.379. I'm not sure which number to multiply this by to get a whole nu...

Rachel McMillan 3A

On problem #15 in the Chapter 1 homework, we were given a value of 102.6 nm as the wavelength and were asked to find the initial and final energy levels of the electrons. I first multiplied 102.6 nm by 1x10^-9 to convert the wavelength into meters. I then used the equation 1/wavelength=RZ^2((1/n1^2)...

CHEMISTRY COMMUNITY

Search found 26 matches

Naming compounds with cyclo substituents

Re: Calculating concentration #23c

Calculating concentration #23c

Calculating q

Quiz #3 Prep #5 priority on alkanes??

Organic Molecules naming of compounds, numbers

When there are fractions [ENDORSED]

Affect of precipitation on cell potential

Calculating work from expansion 1st Quiz, #4

Calculating Bond Enthalpy Quiz #1 Problem #2

Calculating Q

Calculating reaction Gibbs free Energy and n

Quiz Winter 2014 #11 Finding Final Volume

Homework 8.27 Reversible expansion calculations

Enthalpy of Physical Change self-test

Reversible and Irreversible Reactions Definition

Molecular Orbital Theory Video

Re: Video: Applying Le Chatelier's Principle to Photosynthei

Re: Video: Applying Le Chatelier's Principle to Photosynthei

Finding K to see if products or reactants are favored

Writing formulas from compounds with "bis"

Q vs K

Strengths of Repulsions

Resonance Stucture Stability

Finding Empirical Formulas when mass % does not add to 100%

How to find beginning & ending energy levels with wavelength