DINO NUGGETS Review Session! Download Problems HERE [ENDORSED]

[Chem_Mod]

The title is called "Dino Nuggets" so that you can search "Dino Nuggets" and easily find this post!

This is your favorite UA, Lyndon Bui, and here are many practice problems for your midterm. The questions are modeled after previous test and exam questions, but it may not have everything you need to know. This covers only material for the midterm.


Please complete these problems before my review session. My review session this quarter (Fall19) will be Friday, Nov 1, from 5-8pm in Moore 100. I will go over each problem in detail during my review session. The answers, but not full solutions or work, will be posted here at this post after the review session. Any errors in the test will be posted below as well.

Printed copies will NOT be provided at the review session.

This quarter, the review session will feature not just me, but three other UA's! What fun!

Link to Download Problems:

PracticeMidtermFall19_20.pdf

(170.58 KiB) Downloaded 2353 times

Mini Dino Nuggets.pdf

(126.96 KiB) Downloaded 1096 times

*Mini Dino Nuggets contains supplemental questions that cover material that was not on the original problem set.

***This is not indicative of the structure, length, or format of the actual midterm. Treat these as extra practice problems. ***

Errors: 13 c) Error found - Please change "throws" to "yeets" (Error caught by Matt Tran)

Link for Answers:

Dino_Nuggets_Answer.pdf

(132.99 KiB) Downloaded 1409 times

Mini Dino Nuggets Answers.pdf

(189.28 KiB) Downloaded 819 times

Happy Studying and Good Luck!
-Lyndon Bui, UA

[Daniel Yu 1E]

Where can I find the review problems? Also, how do I download the problems?

Chem Mod: Please simply scroll up and read the post! Everything you've asked is there.

[melinak1]

I have class until 5:50 on Friday. Is it still fine if I come to the review session 6-8? What will I miss?

[Jasmine Fendi 1D]

Do you think that the practice problems on the dino nuggets worksheet are about the same difficulty as the problems that would be on the midterm?

[Micah3J]

If I am unable to make the review session tomorrow night but still work out the problems on my own, will the answers be posted on here so I can check my work?

[205150314]

If I am unable to make the review session tomorrow night but still work out the problems on my own, will the answers be posted on here so I can check my work?

Yea it says it right there that the answers will be posted after the review session

[sbottomley3a]

How will the difficulty of these problems compare to the difficulty of the midterm?

[Malik Oda 1F]

Can you please post the work along with the the answers because it was hard to see all the work from the back of the lecture hall

[Janet Nguy 2C]

Does anyone know if the midterm will include our most recent topics like Lewis Acids/Bases, Dipole moments, etc.? Or is the cutoff for drawing lewis structures?

[Joanne Kang 3I]

I believe Dr. Lavelle said that he would not include the last slide he went over in lecture, which was "Interactions Between Ions & Molecules". Other than that I think everything else can possibly be on the test.

[kpang_4H]

How will the difficulty of these problems compare to the difficulty of the midterm?

At the review session, he said the problems just as hard or harder than midterm questions ideally.

[904914037]

I know it says answers will be posted after the review session but does anyone know when exactly they might be posted?

[Chem_Mod]

I know it says answers will be posted after the review session but does anyone know when exactly they might be posted?

Now:) Thanks for the reminder

[Elizabeth Harty 1A]

Can someone explain how to do #5 from this problem set?

[Ada Chung 1C]

Will the mini dino nuggets answer key be posted as well?

[ayushibanerjee06]

Will the mini dino nuggets answer key be posted as well?

Will they be posted? pls help us out

[Bita Ghanei 1F]

Will the mini dino nuggets answer key be posted as well?

Whoever posts the answers, could you please include the lewis structure drawings for 2A with the dipole moments included?
Does anyone know when to draw the dipole moments and which atoms to put them on?

[JOtomo1F]

Will the mini dino nuggets answer key be posted as well?

Will they be posted? pls help us out

Hello! Also just wondering if the mini dino nuggets answer key will be posted anytime soon. Thanks!

[904914037]

Can someone please explain how to solve question 2 from Dino Nuggets? Conceptually, I understand how to solve this type of problem but my numbers keep coming out different so I must be doing something wrong. Thank you!

[205150314]

Can someone please explain how to solve question 2 from Dino Nuggets? Conceptually, I understand how to solve this type of problem but my numbers keep coming out different so I must be doing something wrong. Thank you!

I'm having the same problem, if you found the answer could you please let me know

[Chem_Mod]

Will the mini dino nuggets answer key be posted as well?

Will they be posted? pls help us out

Posted :) Apologies for the wait.

[Naren_Ramesh_4F]

I just wanted to thank the TA who made this because I found this to be an awesome resource for studying. Thank you so much!

[ayushibanerjee06]

For 2a in Mini Dino Nuggets, do you need to draw partial positives on the hydrogens?

[Fdonovan 3D]

Isopropyl alcohol, used in rubbing alcohol, is a compound containing only C, H, and O. What is the empirical formula of isopropyl alcohol if you find that 0.255 g of the compound gives 0.561 g of CO2 and 0.306 g of H2O when burned completely in excess oxygen?

Can someone please help get started on this problem?? Not sure why I’m having so much trouble but I can’t seem to figure out how to isolate O2 and C from CO2 and the same with H2O! Please help

[zfinn]

for dino nuggets #4 why is the answer 2 sig figs and not 3? is it because 250 mL has only 2 sig figs? i'm a bit confused if that's the reason or if it's something else - if someone could clarify that would be great! thanks so much

[205150314]

For Dino Nuggets 6a, what equation do we need to use ? ive been trying to use different one (because theres a lot for E) and that molar mass is messing me up.

[Hailey Kim 4G]

for dino nuggets #4 why is the answer 2 sig figs and not 3? is it because 250 mL has only 2 sig figs? i'm a bit confused if that's the reason or if it's something else - if someone could clarify that would be great! thanks so much

Yes, for #4, the answer only has 2 sig figs because 250 mL has only 2 sig figs. You take the least number of sig figs that are given in the question.

[Hannah_1G]

In the answer key for the mini dino nuggets, the dipole moments in question 2a are going towards the negative partial charge when in the textbook it says to go towards the positive charge. What would be correct?

[Jamie Lee 1F]

Isopropyl alcohol, used in rubbing alcohol, is a compound containing only C, H, and O. What is the empirical formula of isopropyl alcohol if you find that 0.255 g of the compound gives 0.561 g of CO2 and 0.306 g of H2O when burned completely in excess oxygen?

Can someone please help get started on this problem?? Not sure why I’m having so much trouble but I can’t seem to figure out how to isolate O2 and C from CO2 and the same with H2O! Please help

Hi! You would have to use the molar ratio to find how much Carbon is in CO2 in grams, and do the same with H in H2O. Once you find how much Carbon and Oxygen you have, you would add those quantities and subtract it from the total given mass of isopropyl alcohol to find how much Oxygen you have in the sample. Hope this helps!

[Jamie Lee 1F]

Can someone explain how to do #5 from this problem set?

First, you want to find your initial molarity since it isn't given to you. You would use the first set of information to do so. You would have one flask with 5.00 grams of KMnO4 (which you would convert to moles). To find the molarity of this solution you would use M=n/v. This is your initial molarity that you would plug into M1V1=M2V2, as well as the other needed values. Solve to find your final molarity, or M2! Hope that made some sense.

[Jamie Lee 1F]

For Dino Nuggets 6a, what equation do we need to use ? ive been trying to use different one (because theres a lot for E) and that molar mass is messing me up.

I used de Broglie's since light isn't involved. Also, make sure you convert the molar mass to mass using Avogadro's... that also might be messing you up if you haven't done that already.

[zfinn]

Hi! a few more questions on the dino nuggets review - can anyone explain the reason behind the answers to 9.e, 9.f, or 9.h? also 9.j? Thanks so much in advance!!

[Jamie Lee 1F]

Could someone please explain 8b please? I used the photoelectric effect equation relating kinetic energy, energy of the photon, and the work function, but for some reason I'm not getting the correct answer.

[904914037]

Can someone please explain how to solve question 2 from Dino Nuggets? Conceptually, I understand how to solve this type of problem but my numbers keep coming out different so I must be doing something wrong. Thank you!

I'm having the same problem, if you found the answer could you please let me know

I found that if you are given the molar mass of the compound and are asked to find only the molecular formula, you can use the percentages given to convert directly into the amount of grams present for each element, which can then be converted to the moles of each element present which should ultimately be your final answer!

[Micah3J]

Can someone explain to me the concepts behind 10a? I am confused on why it is Aluminum. Thanks

[Micah3J]

Could someone please explain 8b please? I used the photoelectric effect equation relating kinetic energy, energy of the photon, and the work function, but for some reason I'm not getting the correct answer.

What answer did you get? I'm having the same trouble and wondering if maybe we made the same mistake.

[Jamie Lee 1F]

Can someone explain to me the concepts behind 10a? I am confused on why it is Aluminum. Thanks

Aluminum is larger than Silicon because the effective nuclear charge is stronger in Silicon, which means that the electrons are pulled more strongly towards the nucleus mostly because there are more of them (or 1 more in this case). Basically, the more electrons there are, the greater the force of attraction towards the nucleus.
Hopefully this helps!

[Jamie Lee 1F]

Could someone please explain 8b please? I used the photoelectric effect equation relating kinetic energy, energy of the photon, and the work function, but for some reason I'm not getting the correct answer.

What answer did you get? I'm having the same trouble and wondering if maybe we made the same mistake.

I got 3.77 x 10^14 Hz

[AGaeta_2C]

In the answer key for the mini dino nuggets, the dipole moments in question 2a are going towards the negative partial charge when in the textbook it says to go towards the positive charge. What would be correct?

On page 96 of the textbook it shows two. different conventions for representing the dipole. The first is the original convention, in which the arrow points toward the negative partial charge. The second is the modern convention, in which the arrow points toward the negative partial charge. The text uses the modern convention whereas the answer key uses the original convention. I'd say the original convention is easier to convey on paper so that's what I'm going to be using on the exam. Hope this helped!

[lauraxie2e]

For 6D I am still unclear on what it means by wave like properties, could someone explain that to me?

[ayushibanerjee06]

For 6b., I am confused about why GarBreadium has the longer deBroglie wavelength. Shouldn't it be He because it weighs more?

[curry 1E]

for mini dino nuggets 3a and 3b can someone please explain the difference between polarizing power and most polarizable?

[ayushibanerjee06]

Could someone please explain 8b please? I used the photoelectric effect equation relating kinetic energy, energy of the photon, and the work function, but for some reason I'm not getting the correct answer.

i think they used the wrong mass of an electron because when i went to the review session they used 9.11*10^-11 kg instead of 9.11*10^-31 kg. when you use 9.11*10^-11 kg you get 6.78*10^14 Hz. when i use 9.11*10^-31 kg i got 3.77*10^33 Hz.

[205150314]

For 6b., I am confused about why GarBreadium has the longer deBroglie wavelength. Shouldn't it be He because it weighs more?

GarBreadium weighs less so it'll make the denominator smaller compared to the denominator of He so the outcome (length) will be larger than if you were to divide by a larger denominator like He. That is why He has the smaller wavelength

[205150314]

Could someone help me on 8B?

[205150314]

Could someone please explain 8b please? I used the photoelectric effect equation relating kinetic energy, energy of the photon, and the work function, but for some reason I'm not getting the correct answer.

i think they used the wrong mass of an electron because when i went to the review session they used 9.11*10^-11 kg instead of 9.11*10^-31 kg. when you use 9.11*10^-11 kg you get 6.78*10^14 Hz. when i use 9.11*10^-31 kg i got 3.77*10^33 Hz.

Thank you!

[205150314]

Could someone please explain 8b please? I used the photoelectric effect equation relating kinetic energy, energy of the photon, and the work function, but for some reason I'm not getting the correct answer.

i think they used the wrong mass of an electron because when i went to the review session they used 9.11*10^-11 kg instead of 9.11*10^-31 kg. when you use 9.11*10^-11 kg you get 6.78*10^14 Hz. when i use 9.11*10^-31 kg i got 3.77*10^33 Hz.

Thank you!

SO idk how but ive used both 9.11*10^-11 and -31 and still recieve the exact same answer for both masses how is that possible ?

[AGaeta_2C]

for mini dino nuggets 3a and 3b can someone please explain the difference between polarizing power and most polarizable?

Polarizing power is used when referring to cations, which give up an electron. Polarizability refers to anions, which gain an electron. These terms both point out the covalent character of some ionic bonds. Polarizing power is the ability of a cation to pull electrons (smaller, more positive cations pull more strongly). Polarizability is the willingness the anion has to have its electron pulled (larger anions hold less strongly to their outer electrons).

[Jared Khoo 1G]

For 6b., I am confused about why GarBreadium has the longer deBroglie wavelength. Shouldn't it be He because it weighs more?

As mass is on the denominator for deBroglie wavelength calculations, a lower mass atom will have a longer wavelength as it is inversely proportional.

[Micah3J]

What is the limiting reagent for #3? Thanks, i just want to be sure I'm doing it right

[VioletKo3F]

Does anyone know the answer to 11a?

[205150314]

Does anyone know what to do for 13a?

[Micah3J]

For Dino Nuggets 6a, what equation do we need to use ? ive been trying to use different one (because theres a lot for E) and that molar mass is messing me up.

I used de Broglie's since light isn't involved. Also, make sure you convert the molar mass to mass using Avogadro's... that also might be messing you up if you haven't done that already.

How do you convert the molar mass to mass? I'm having trouble using Avogadro's number