Calorimetry Concept, Examples and Thermochemistry | How to Pass Chemistry

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Melissa Maribel

Melissa Maribel

Күн бұрын

Пікірлер: 142
@melissamaribel
@melissamaribel 6 жыл бұрын
At 5:07 it's supposed to be 36.218 Tf instead of 36.2108 Tf
@arnalis9949
@arnalis9949 5 жыл бұрын
Chemistry with Melissa Maribel Calculate the enthalpy of the reaction,​​​​​ (3 points) 2SO2(g) + O2(g) -> 2SO3(g) ​given the following data: S(s) + O2(g) ->SO3(g); H1 = -395 kJ S(s) + O2(g) ->SO2(g); H2 = - 297 kJ
@gabrielamarquez8934
@gabrielamarquez8934 5 жыл бұрын
Hi Melissa When dividing -440.5752 by 12.5125 I actually got -35.2108 did I do something wrong?
@ishwarydeepak123
@ishwarydeepak123 5 жыл бұрын
@@gabrielamarquez8934 no you didn't. There is a typo in the video. I did this multiple times and got the same answer
@faustinamercynongspung6387
@faustinamercynongspung6387 3 жыл бұрын
Mam can you take class for physic also .
@yaqubburhan7858
@yaqubburhan7858 2 жыл бұрын
32.5 × 0.385 is 11.635, and you write 12.5125 . Is there's something wrong 😕 🤔?
@donnam6889
@donnam6889 6 жыл бұрын
I cannot tell you how much you have helped me!! I am going back to college after 20+ years and DREADED taking chemistry. Got an A on both Exam 1& 2. Dancing for joy!!
@samiramirez5659
@samiramirez5659 5 жыл бұрын
you just taught me in less than 10 minutes what my professor failed to do in 2 weeks
@notchoc0
@notchoc0 5 жыл бұрын
My mind is blown you really know how to make the concept so much easier ;A; THANK YOU!!
@ritwikjana2841
@ritwikjana2841 5 жыл бұрын
I am an Indian and I really feel we should have a u tube teacher like u 😍in love with ur voice and way of teaching 😘😘😘😘
@katebrunton9834
@katebrunton9834 Жыл бұрын
i was worried about my college chem exam but i’m okay now because you’ve got me! thank you FOREVER
@hennesey5928
@hennesey5928 5 жыл бұрын
i had the biggest sigh of relief when i found you taught this lesson. your content is great. Thank you so much
@jennac4899
@jennac4899 5 жыл бұрын
Melissa, you are a saint. You have not only helped me better understand Chemistry and its concepts, but you have helped me gain a newfound confidence as well. Nearly a decade of Depression took a huge toll on my academics. I went from a straight A student who excelled in science to nearly failing all of my classes including science. Attending college as a Chem major was nerve-wracking, but thanks to the help of your videos (and treatment!) I am back to straight A’s and am thriving!! So thank you, Melissa. We all appreciate everything you do. :)
@zeelpatel8210
@zeelpatel8210 3 жыл бұрын
this is so much easier to learn if explained like this. Thanks so much!!
@hayleysalazar4397
@hayleysalazar4397 5 жыл бұрын
You know I'm your #1 fan! Thanks so much for the Calorimetry Concept video! Now I don't need to lecture-- instead, my students get to watch your video, take notes, and practice! Thank you once again for making life easier for this ol' chemistry teacher! Keep dancing!
@melissamaribel
@melissamaribel 5 жыл бұрын
Haha! Thank you Hayley 💕
@bigt7706
@bigt7706 3 жыл бұрын
It never dawned on me that the two Tf's were like terms, thanks so much for explaining it clearly!
@MarciaArleneDebra
@MarciaArleneDebra 6 жыл бұрын
I like the simple practical example at the start. I work best by understanding procedures, and the example satisfied that need. It took the place of an avatar who would have asked for explanations. A brilliant presentation
@melonkitty12345
@melonkitty12345 3 жыл бұрын
Wow, you just blew my mind. I’ve been racking my brain on how to solve these the way my professor showed us and you just made it so simple! Thank You!! 😭
@ArtSmartAcademyIrmo
@ArtSmartAcademyIrmo 3 жыл бұрын
If you use 35.218, then the next step changes to 542.3572 (Your prep people are not staying consistent). They used -440.575/12.5125=-35.21078921*-15.4=542.24632...I caught it, but some newer folks might be confused why the numbers are not consistent. Thank you for all you do to make CHM AMAZINGLY FUN!!
@lexiedang6965
@lexiedang6965 5 жыл бұрын
You are awesome. I learned so much by watching your videos. Thank you so much everything you do .....
@Maryamhassan310
@Maryamhassan310 6 жыл бұрын
I love you, you're sucha life saver. You make chemistry SO much fun and vibrant, and I realllly like that you are to the point and clear
@melissamaribel
@melissamaribel 6 жыл бұрын
Aww thank you so much Maryam 😊Happy you like my teaching style & video style 💕
@nnekababy
@nnekababy 5 жыл бұрын
Seriously...I've been trying to figure this out for two days...and then you appeared. I don't know if it's the colors or the dancing but I understand this so much better than my instructor's videos.
@melissamaribel
@melissamaribel 5 жыл бұрын
It's probably the dancing 💃🏻😂
@KARINAAMAYA-i9q
@KARINAAMAYA-i9q Жыл бұрын
Thank you!! so helpful
@sreenidhi9093
@sreenidhi9093 3 жыл бұрын
1:37 Can someone explain why is q metal = -q water here?
@vonwachnacht
@vonwachnacht 4 жыл бұрын
Thank you so much! Much needed lesson, without it I'd bomb my test.
@brenda.rodriguez2003
@brenda.rodriguez2003 3 жыл бұрын
I love how she starts with a cup of coffee for an example after I just watched the advertisement for her video to stop drinking coffee.
@maxsimbalassone2700
@maxsimbalassone2700 2 ай бұрын
I’m watching this the day of my midterm!
@danielspence1119
@danielspence1119 3 жыл бұрын
How did you get 36.2108 from +45.8 to both sides
@danielspence1119
@danielspence1119 3 жыл бұрын
& what happened to the -35.218
@mateo8559
@mateo8559 3 жыл бұрын
Much love from chemistry UIC students!!
@alyciamcneil1044
@alyciamcneil1044 4 жыл бұрын
Thank you so much I learned so much!📚
@lexbuckaloo4052
@lexbuckaloo4052 5 жыл бұрын
Thank you so so much!!! It helped me a lot!
@michaelgalario6655
@michaelgalario6655 3 жыл бұрын
Hi! I would just like to know whether there is a difference between using the Big Q and the small q in the equation? For example in computing latent heat Q = mL, it uses only big Q for heat energy, but for q = mcΔT, I have been seeing some use Big Q and others small q. Thanks!
@jaafarhire5837
@jaafarhire5837 Жыл бұрын
How will u calculate enthalpy change if u are given specific heat capacity and heat capacity of calorimeter
@levi-hi6js
@levi-hi6js 5 жыл бұрын
Thnxxxxx....uh hve made all my concepts clear.. Thnx once again...ur voice always motivates me..... Thnx once again 😊😊😊😇😇
@melissamaribel
@melissamaribel 5 жыл бұрын
You are so welcome!
@levi-hi6js
@levi-hi6js 5 жыл бұрын
@@melissamaribel my pleasure😇
@mirazwrld3764
@mirazwrld3764 2 жыл бұрын
Do you have a video for finding molar mass?
@melissamaribel
@melissamaribel 2 жыл бұрын
Yes search “molar mass Melissa” on KZbin
@jessevaldez1657
@jessevaldez1657 4 жыл бұрын
Shouldn't the exercise problem at the end be only 1 Sig Fig because of the 60g given?
@DerangedIntellectual9
@DerangedIntellectual9 3 жыл бұрын
Thank you, Professor Maribel
@bluebird8405
@bluebird8405 4 жыл бұрын
Hi, I'd like to clarify. Isn't the metal should bear the negative sign since it is the one that releases heat and the water should have the positive sign since it absorbed the heat from the metal?
@olgazenteno8825
@olgazenteno8825 3 жыл бұрын
yes it is q metal gives heat therefore negative...q plus to the water
@nothandozwane3079
@nothandozwane3079 3 жыл бұрын
Thank you! You made it easy to understand. Can i please ask a question, when do we add the mass of the substance and to water to get total mass of the solution? Thank you x
@johnmichaeltondo9052
@johnmichaeltondo9052 9 ай бұрын
Hi there, can I ask why you put a negative sign on the side of the water? It seems that the metal should have a negative sign since the heat is flowing from hot to cold. (Negative sign indicating that exothermic process happened) Can you clarify this?
@emilyreinel
@emilyreinel 5 жыл бұрын
Thank you so so so much. Your videos always help me out a ton ! :)
@nthumara6288
@nthumara6288 Жыл бұрын
is this heat capacities for constent volume or for constent pressur
@banzilwillienwyethi.270
@banzilwillienwyethi.270 4 жыл бұрын
how can i determine the mass of water used in the reaction? note: it's not given in the question
@shawnong7287
@shawnong7287 3 жыл бұрын
will the steps be same if initial temperature is missing?
@tshepangngwatoana3075
@tshepangngwatoana3075 4 жыл бұрын
This was very helpful for me thank you a lot
@marielbarba5597
@marielbarba5597 3 жыл бұрын
In your example, if the substance released the energy should the value of Q is negative?
@Jesus_Paid
@Jesus_Paid 6 жыл бұрын
nails, dance moves and teaching skills on fleek!
@melissamaribel
@melissamaribel 6 жыл бұрын
Haha thank you! 💁‍♀️
@teedubya90
@teedubya90 4 жыл бұрын
if you distribute 35.218 to the left side wouldn't it be -10.582? just confused on how you got 36.2108. thanks for the help
@christinalabarbera44
@christinalabarbera44 4 жыл бұрын
Same
@alyssaallengaskill6116
@alyssaallengaskill6116 4 жыл бұрын
In the problem I'm given by my school the specific heat of the metal (NaOH) isn't supplied in the question, do you have a video that goes over how to find that?
@elenamatarazzo8293
@elenamatarazzo8293 7 жыл бұрын
enthalpy pls!
@NovaWarrior77
@NovaWarrior77 6 жыл бұрын
I agree!
@alexism7294
@alexism7294 5 жыл бұрын
Could you please explain how to determine where to put the negative symbol? Does it really matter/would you have gotten the same answer if it was -qmetal=qH2O
@melissamaribel
@melissamaribel 5 жыл бұрын
Either way will give you the same answer, the negative depends on the question, but just know that one is negative and the other is positive and you will get the same answer each time.
@alexism7294
@alexism7294 5 жыл бұрын
@@melissamaribel awesome, thank you!
@dayanpuentes2665
@dayanpuentes2665 5 жыл бұрын
Hello, I am new here. Thank you very much. it helped me a lot. I have a problem with the practice question, I did step by step but the answer was different. it was 55.5 Celcius and you have 50.2 Celcius. can you help me?
@rebeccaowens6581
@rebeccaowens6581 4 жыл бұрын
yes same!!
@brenda.rodriguez2003
@brenda.rodriguez2003 3 жыл бұрын
I have a question if water is gaining heat wouldn't q be larger than 0 aka positive because it's endothermic. It's what is on the ppt from my class.
@eviedson
@eviedson 4 жыл бұрын
Wait, but wouldn't the negative be for the heat of the metal because its the one losing heat the water is absorbing it?
@adriang.4628
@adriang.4628 2 жыл бұрын
can you do an example with a phase change? specifically vaporization?
@janvieremmanuel6788
@janvieremmanuel6788 4 жыл бұрын
you the best Melissa 100000000%
@nthumara6288
@nthumara6288 Жыл бұрын
why we use two terms called moloer heat capacity and specific heat capacity
@yoitsrami
@yoitsrami 5 жыл бұрын
All I'm saying is: "You can't have the guaca-MOLE without the ava-CADO!" *Proceeds to throw guacamole into Melissa's face* lmao
@melissamaribel
@melissamaribel 5 жыл бұрын
😂😂😂
@jaynamichaels6446
@jaynamichaels6446 5 жыл бұрын
How do you know which one is positive or negative
@alexia5141
@alexia5141 6 жыл бұрын
Isn't it the other way around? Qwater= - Qmetal because heat is being released from the metal (exothermic) and the water is absorbing the heat (endothermic).
@alexia5141
@alexia5141 6 жыл бұрын
Oh alright! Thank you for the quick reply. I'm getting ready for a final exam tomorrow. This really helped!
@alexia5141
@alexia5141 6 жыл бұрын
Melissa Maribel thank you! It went well because of this video!
@jessicamiller5202
@jessicamiller5202 6 жыл бұрын
Alexia what was her answer? I can't see it and I had the same question
@melissamaribel
@melissamaribel 6 жыл бұрын
Both work they will give you the same answer, I've seen it written both ways but the main thing to know is that they are opposite signs.
@TheRoseluv33
@TheRoseluv33 5 жыл бұрын
howd you get the practice answer? i got 10.416 :/
@allergictokiwi
@allergictokiwi 5 жыл бұрын
I got this answer too! Did you figure out how to get the right answer? Someone help us :(
@nthumara6288
@nthumara6288 Жыл бұрын
what is molor heat capacity
@chipmunk9996
@chipmunk9996 6 жыл бұрын
You are amazing! Thank you so much!!! :)
@christinalabarbera44
@christinalabarbera44 4 жыл бұрын
Ok so I got 35.2108(-440.572÷12.5125 is 35.2108) not 35.218 firstly but that's but I think you know this. But how did you get 36.2108 from 35.2108? Where did the 1.0 come in at the end?Tried a few ways but can't get it. By the way my college referred us to your videos. Your videos are really helpful especially in times like this.
@YadoOrTAE
@YadoOrTAE 2 жыл бұрын
Same. I’m thinking combine like terms mean add +the negative, and the number goes down not up
@abhimanyugupta238
@abhimanyugupta238 5 жыл бұрын
you are a life saviour
@self-loveletters6313
@self-loveletters6313 5 жыл бұрын
can the same thing be said when finding specific heat? is it just solving for Cs??
@melissamaribel
@melissamaribel 5 жыл бұрын
You would have to be given one of the Cs values, and only have one unknown Cs.
@Ana-lo8yx
@Ana-lo8yx 4 жыл бұрын
I have a question, how do you distribute? In case you can’t tell, I’m new to chemistry and when I multiplied, I got a flat 524. By the way, love your videos! After trying out the practice problem myself, I got 43 instead of 50.2. Is there anyway you could explain to me where I went wrong?
@jackgramins6248
@jackgramins6248 4 жыл бұрын
Who's watching this because they have a test tomorrow?
@elaafalmalek7401
@elaafalmalek7401 5 жыл бұрын
My steps are right the my final ans was wrong 🤦🏻‍♀️ 0.o
@YaCzarnaPantera
@YaCzarnaPantera 5 жыл бұрын
THANK YOU!
@jatrishaeckford6319
@jatrishaeckford6319 5 жыл бұрын
How did you get 0.385 and 4.184 for the first problem?
@melissamaribel
@melissamaribel 5 жыл бұрын
This is given, this is the specific heat capacity for the copper and water. You typically are expected to know the specific heat capacity of water 4.184, but all others must be given to you.
@nike.0rtiz
@nike.0rtiz 4 жыл бұрын
Chemistry killed my love for science
@josephl.respicio9297
@josephl.respicio9297 4 жыл бұрын
Excellent
@domenicasilva6368
@domenicasilva6368 3 жыл бұрын
Why divide 12.5? Why not subtract from each side?
@disteve2466
@disteve2466 4 жыл бұрын
A 23.9 g silver spoon is put in a cup of hot chocolate. It takes 0.343 kJ of energy to change the temperature of the spoon from 24.5 °C to 85.0 °C. What is the specific heat capacity of silver? (Answer: 0.237 J/ g °C) csilver = 0.240 J / g °C If there is a question like this, why do i need to find the value of the heat capacity when silver's heat capacity is shown and given.....I mean the heat capacity is the amount of heat that can hold in a substance and when the temperature exceed the amount of heat that substance can hold, the temperature rise up by one degree and mass..but how come the heat capcity change when the temperature increase? idk......i have no idea plz share some opinion or answer.....e
@rayamoooooo685
@rayamoooooo685 5 жыл бұрын
*in response.. Am i q or your channel q, or am i -q or your channel -q, may be equilibrium, anyway..* Aweeeesome!! and oh how desperate i was for another sample question 😝
@thisguy9591
@thisguy9591 5 жыл бұрын
Where did you get the 105.3???????
@melissamaribel
@melissamaribel 5 жыл бұрын
At 2:36 you will see that it was part of the original question
@kelseylee2550
@kelseylee2550 5 жыл бұрын
omg thank you so much
@jeannineflores7067
@jeannineflores7067 7 жыл бұрын
Could you show your worked out answer for the end of the video please. I'm not getting your answer and I'm trying to figure out my missed step. thanks
@TasiaMarieTv
@TasiaMarieTv 6 жыл бұрын
On the answer key you divided by the negative number -251 of thr water. In the video you divided by the positive number of the metal. How do you know which to divide by?
@upulaherath7204
@upulaherath7204 4 жыл бұрын
I wish all my lectures are pleasant and beautiful like you!!!
@melissamaribel
@melissamaribel 4 жыл бұрын
Thank you!
@demetrik8642
@demetrik8642 4 жыл бұрын
Would the metal not be the one that is negative? My professor lectured in a way that whatever is giving off heat will be the negative q and whoever is absorbing the heat is positive. Not sure if she's crazy or what lol
@thesevenseasofcale2759
@thesevenseasofcale2759 5 жыл бұрын
you are a GODDESS
@melissamaribel
@melissamaribel 5 жыл бұрын
Aww thank you Caley 💕
@thesevenseasofcale2759
@thesevenseasofcale2759 5 жыл бұрын
update:i watched this video the class before i had a chemistry quiz and i got a 73 (a lot of people didn’t do well)
@melissamaribel
@melissamaribel 5 жыл бұрын
Glad you passed it!
@thesevenseasofcale2759
@thesevenseasofcale2759 5 жыл бұрын
update 2:i got the highest quiz grade
@guadalupecarrillo9218
@guadalupecarrillo9218 6 жыл бұрын
In the example problem you made a mistake when writing the numbers out. Did you confuse -35.218 for 36.2108
@guadalupecarrillo9218
@guadalupecarrillo9218 6 жыл бұрын
Thank you for clarifying, that makes so much more sense. I love your videos by the way!
@maxinedominiqueoropel1181
@maxinedominiqueoropel1181 6 жыл бұрын
I think the mistake I see in your calculation is that you wrote -35.218 instead of -35.2108 before adding (after transposing) it to 1Tf. 36.2108 is 1 plus 35.2108, not 1 plus 35.218 (that would 36.218 instead). Other than that, thank you for this video. I have to admit, the first few times I had to deal with the formula were a struggle. I now understand how to solve with the formula thanks to this.
@ruger51995
@ruger51995 4 жыл бұрын
Hi so your example is the best one the others use two variables like adding water to water but this one is the most common one asked and is broken down to a newbie level which is great and also these numbers are the exact same of the one im working on for a take home quiz exc pt it's with aluminum and it's Cs of course, the beginning part almost turned me off, you might get alot of people.more impatient than me, just a suggestion to think about, nothing too bad though 😁
@Shyheimlovesgames
@Shyheimlovesgames 4 жыл бұрын
where you get 0.385
@daien2033
@daien2033 5 жыл бұрын
What's endothermic and exothermic?
@DerangedIntellectual9
@DerangedIntellectual9 3 жыл бұрын
I find it funny how many of these youtube videos you're able to watch for FREE are able to help you learn better than the university and profs you PAY to teach you :/
@ahahahahah650
@ahahahahah650 5 жыл бұрын
I wish I had found you sooner!
@AF-hv4yy
@AF-hv4yy 2 жыл бұрын
I feel like I'm stupid bc I still don't get it
@meganpinkus9323
@meganpinkus9323 7 жыл бұрын
please do empirical formula im dying
@KBerm
@KBerm 3 жыл бұрын
After watching this I'm sure I'd be better off watching 20m KZbin lessons than a 2h lesson with my proffesor
@jessicaking9350
@jessicaking9350 6 жыл бұрын
can you do more videos on thermochemistry please
@melissamaribel
@melissamaribel 6 жыл бұрын
This topic is definitely on my list of videos to make more of this semester!
@gibrielbenjamin6680
@gibrielbenjamin6680 6 жыл бұрын
I need the title of the break dance song
@melissamaribel
@melissamaribel 6 жыл бұрын
Here's all the music I used in this video: Song: Cjbeards - Winter Breeze (Vlog No Copyright Music) Music provided by Vlog No Copyright Music. Video Link: kzbin.info/www/bejne/hnS9gp-OeMd6pq8 Always (Vlog Music) by Dj Quads soundcloud.com/aka-dj-quads Music promoted by Audio Library kzbin.info/www/bejne/oHrMdmSbr89nmdU
@lexlovesmovies
@lexlovesmovies 5 жыл бұрын
Hi I'm super confused about your math at the end
@melissamaribel
@melissamaribel 5 жыл бұрын
Hey Alexis what part exactly were you confused on?
@lexlovesmovies
@lexlovesmovies 5 жыл бұрын
@@melissamaribel I'm confused on how you went from Tf - 45.8 = -35.218Tf + 542.24632 to the next step. I am confused on the exact math. I tried it over and over again and I got random numbers.
@melissamaribel
@melissamaribel 5 жыл бұрын
@@lexlovesmovies There was typo that I mentioned in the comments at this part, At 5:07 it's supposed to be 36.218 Tf instead of 36.2108 Tf. That could be part of the confusion.
@hiwakarem7640
@hiwakarem7640 4 жыл бұрын
very good , are u marid?
@callmetatopls
@callmetatopls 4 жыл бұрын
be my teacher 🥺
@pinkbubba6452
@pinkbubba6452 5 жыл бұрын
i got -12.91C im soooo off
@pepitobenegas
@pepitobenegas 5 жыл бұрын
chemistry is the most ridiculous science. I feel that its only purpose is making things more complicated than they are. Anybody can learn it, it is just that they love making things more complicated.
@themillennialpa
@themillennialpa 6 жыл бұрын
You are so smart. Can I have your brain
@melissamaribel
@melissamaribel 6 жыл бұрын
Thank you, You can't have my brain but you CAN reserve it for an hour on my patreon page 😂😂 www.patreon.com/
@flintfury7634
@flintfury7634 9 ай бұрын
I still don’t understand this topic frustrates me so much you have no idea doing this makes want to tear my hair out😡😡
@soykillerqueen
@soykillerqueen 4 жыл бұрын
Excuse my ignorance, but isn't the negative sign in - q water = q metal supposed to be switched or does it not matter? My chem lab book has the negative sign in front of q metal. edit: I think it may have to do something about the order because the equation in my book goes like this: + q water = - q metal
@Sheamber
@Sheamber 5 жыл бұрын
now i am in CHEM 152... I AM NERVOUSS I HAVE AN 89 in it and this is my second week! do you tutor live anywhere or meet up with people?
@melissamaribel
@melissamaribel 5 жыл бұрын
I don't tutor one on one anymore but I do have a playlist for Chem 2 that will help ➡️kzbin.info/aero/PLytGGifnD9dUBS_c-lV3Z_F1A9D9SDmHp
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