I love how he explains things as if I were 7 years old but without it seeming insulting

Jesus coming to save me for my chem exam lmfao

Most underrated science channel. College hack

I owe so much to your channel, Professor. Your videos are direct and very easy to understand. I'm studying for an admission test and you have been such a big help.

I had to miss a class on this yesterday. What I watched in this 4 minutes taught me almost everything that my classmates learned in 2 two hours. Thank you so much!

I watch the ads all the way through to make sure my chemistry Jesus gets his Adsense 🥺✨

I'm so glad I found this channel BEFORE my final exam! Cramming for a midterm tonight and I've learned so much in just one hour. THANK YOU!

Dude you are a beast man. Your videos are short and sweet goes straight to the point, keep it going David Grohl.

I'm going back through material to study for my ACS exam for GenChem II, and he has been an incredible help. He explains concepts and equations so simply I don't feel like I have to spend hours trying to figure it out. Thanks Professor Dave!

This taught me more in 4 minutes then my chemistry teacher has taught me all year

Your vids are making my MCAT prep more feasible. Thanks!

You explained this in a 4 minutes video better than a 2 hour lecture by my professor

i manifest that i will have 96 and above grade in advance chemistry, pls lord🙏🙏

Shouldn't the 2nd answer at 3:10 say that the delta H is -1780.6kJ, not kJ/mol? It is still -890.3kJ/mol regardless of how many moles you combust, correct?

2:32 Thanks Dave, this is the first time I learned the difference between dietary calories and chemistry calorie.

This man taught me thermodynamics in half an hour which my chem teacher couldn't in half a month. U r amazing sir ! Keep up the good work!!

Tbh I stil dont understand what I'm doing

Not sure why I need to attend school anymore? I just learnt more in 58 seconds than I have all semester. Thanks for being the awesome science teacher that don't have!

when he said delta H is energy in bonds of product - reactant that just saved my life

Any Indian here?

Thankyou for the video on Thermochemistry: Heat and Enthalpy.

Very informative series. The men like PROFESSOR DAVE are the essence of the humanity. If he continues to lots of other chemical topics he will be welcome. May God bless him time and enthusiasm to teach many other difficult topics in physical, inorganic, organic and applied chemistry.

Thank you.This video was helped me lot to clarify my answers.This is the best channel for science students.

at 3:45 why did you change delta H to a positive in the actual equation when it was originally a negative ?

I love this guy videos. He can explain everything very clearly.

Your videos are my holy grail, thank you so much!~ You explain it so clearly & the visuals help so much.

Studying for ap chem test this is really coming in clutch

this was so clarifying and concise thank you sir

Hi sorry but i dont understand how dix you find this result attend the end or thé video , can you please explain it ? 3:44

Correct the unit of it :- ∆H = -890.3 KJ/mol

Thank you so much for your videos sir, your videos have been very useful for both physics and chemistry in my current academic year.

Thank god there are people like professor Dave who can actually explain the material eloquently and in an interesting way and not bore you to death like my stupid chemistry teacher in school.

2020 and he's still the best!

This is exactly the information I was looking for. Thank you!

The explanations helped me a lot, however the "comprehension" I had trouble with because I learned it much differently

I finally understand enthalpy from ur 4min vid, and its better than those 40min or hour and a half crappy vids!

Thank u so much. So impressive and easy to understand

If a chemical equation has a delta heat value given, if the heat value is negative, does that mean the reaction is exothermic? just double checking, it can be kinda confusing, i love your videos thanks!

the most important point in thermodynamics you said ,.. thanks Prof. Dave!!

What is the difference between q and H when both are defind as energy

Professor Dave is the GOAT.

Hi can you please explain the comprehension part to me, I don't understand the method that you used?

Wish I found these videos 3 months ago. This is so helpful! But quick question. Why do we keep a positive answer? If the Delta H is negative and its Exothermic, shouldn't we right the number as a neg? If the problem had stated that 890 were positive, would the 556 have been negative? Whats the relationship there in writing the answer with the correct sign(_/+)?

im currently a student living off of subsidies but i promise! when i get my first paycheck when im graduated! i WILL make a donation to you to THANK YOU!

Hi could you pleas walk me through the calculation. I get that 16.0 g is the molemass but why divide everything by 1 mole? If use the formula m/M = n then n X 890 i get the same answer but units won't match.

Love from India professor your teaching is So Amazing

Thank you so much for these great videos. Summing up with the comprehension check is awesome! Very very helpful! Thank you.

Chemistry Jesus. Thank you!

I am so thankful for this video man

I still don’t get it 🙃🙃🙃 is there any other topic I should know before this one to understand it better

Bill gates wants to recreate butter with this.

from where did we get 16g f NH4 in the comprehension question

Good video. Could you please answer my question professor or anyone who is an expert? So if enthalpy of products is lower that means (u+p*rho) is lower. But the fact that heat is released and the temperature of products is higher means that "u" or internal energy must be higher! How do I reconcile these two ?

Q = △H when T and P are constants ? Have just P as a constant is sufficient, no ?

Please prof. Dave explain why there is 16.0g CH4 and it is coming from.

Thanks for this video!

Can someone help me through this dilemma? Work is defined as the (W = F * s) when a body moves a straight distance under a constant force. However, since for a curved path of varying force, we break down the curve to infinitesimal segments where the Force is locally constant and the distance (ds) is essentially straight. Thus, for this tiny line segment, we apply the Work concept and we have dW = Fds. Summing up all the dW would give us the total Work. This is why dW = Fds (and never dW = Fds + sdF). I have the following problems: Under what circumstances is Enthalpy explicitly defined for a system? How can we say that dH = du + PdV + VdP when we never say dW = Fds + sdF?

Just to make sure, I thought that, if the energy of the bonds in the products is greater than the energy of the bonds in the reactants then it should be exothermic and viceversa would be endo. Am I wrong?

Is the amount of heat denoted by q is the same as H (enthalpy) contained in the law of ΔH=Hp-HR In short, is the amount of heat q the same as the enthalpy H?

2:30 You need to have "enthalpy" or "heat" at the top of the background when you are giving definitions/units..i kept having to rewind to see what you were referring to.. every "slide" should have what you're referring to so that each slide can be standalone.

Thank you Professor Dave for your explanation of enthalpy. Could you please make a video to explain effect of expansion valve in thermodynamics. what kind of effect it does on gases and gases take energy from surroundings.

Why is it said that it is not possible to measure enthalpy, but only the change in enthalpy, when enthalpy is equal to the amount of energy stored in one mole of a substance? This means that when energy is measured in a substance, we know the enthalpy of a substance. Is this true?

For those who are confused about conventions and saying the conventions in physics and chemistry are different It's same . It's different because of the different way we deal those things in physics and chemistry. We focus about the change of internal energy in chemistry but we focus on the heat and work done by gas in physics. for eg When heat is supplied to a system of gas and it expands , in chemistry we write ΔU = q - W (W as work done by gas) So If I add Heat to system it;s internal energy increases , right ? So ΔU should be positive (U2-U1) U2 will be greater than U1 . So change will be positive .So , there's a positive sign. And When gas does work , it's spending it's internal energy to do work . So , if you hadn't supplied heat to the system , ΔU will be negative , (U2-U1) , as U1 is greater than U2. So that's it. ΔU =+q - W So for the same scenario in Physics (Adding heat to the system and gas doing work ) , this would be the gas Added Heat = Positive change in Internal Energy of gas + Work done by gas It's the same as if you had $200 and you spent $100 on foods and $100 on rents. SO $200=$100+$100 You gave something , you get the things out of the same worth . So in Physics that would be Q=ΔU + W Notice the + there. It's not convention there. It's a simple math like I did in above money example. Let's make this exact same thing like I did for chemistry. When I put "W" on Left hand side , It will become , Q-W =ΔU Same equation I hope you understood. So again, it's not the convention. It's how we deal with them. But it's easy and time efficient if we deal them differently using the conventions.

Sir i just have one request can you please make a Playlist !!!

Thank you Professor Dave

Professor Dave, you're the man.

Seen once. Shall be seen again. Good vid.

2:29 My mind just exploded

Thanks, you're better than my actual professor.

Thank you Proffesor for helping us😁 in this subject,

love that opening 😂

Thank you for existing

I have a question, Don't you have to know the aggregation state to calculate enthalpy? Or is there a way to know it without it being mentioned in the question ...

+Professor Dave, do you have any videos where you talk about nutrition and exercise? I want to know more about ketogenic diet, muscle building and healthy foods.

Thank you

In this equation ΔH = (q + w) + PΔV: Can someone please explain the difference between work that is part of the internal energy and the other PΔV-work?

is there any terms that define the property of material,if it requires 60 sec to change the temperature by 1 degree in ambient air.

At 00.40, deltaH is described as the energy stored in bonds of products minus the energy stored in bonds of reactants. But how can energy be stored in bonds? Since formation of bonds releases energy, bonds should be defined by the amount of energy they RELEASE and not by the energy they possess. Am I right?

someone explain the comprehension part is that a formula i have yet to learn?

How come entalphy and heat transfer are equal at cnst pressure and temperature

Great explanation, but I still have no idea how to do the qn at the end >.

if delta H for 1mole is negative , the energy is realesed from the systeme therefor it's an exothermic reaction so how could the enthelpy be negative for anoother amount of energy

what is the difference between enthalpy and amount of heat tranfere

Good

how can we measure the change in enthalpy if we can't measure the enthalpy?

Very nice your teching .

I really like this channel; however, the first part about bonds has an issue. Bonds do not "store energy." It takes energy to break bonds; it releases energy to form them. So to keep with the correct sign convention, an approximation of enthalpy should be reactant bond energies - product bond energies, NOT product bond energies - reactant bond energies.

I can't understand one thing. if more energy is released so will the bonds formed be stronger than those broken . If so how can it be true when it looses its enthalpy content

Damn man your videos really helping out for jee

Sir u are the wonderfull teacher awesome sir

Hi sorry but i dont understand how dix you find this result attend the end or thé video , can you please explain it ?

Hi sir, I watched your heat and enthalpy video at now, that is really very nice sir however in your end of the video you gave the comprehension question for find the answer and at the same time you are giving answer also but i don't know how do i find the answer so would you please explain the heat formation and how did you are calculated the answer from the comprehension

Nice , now I am little bit clear with enthalpy, but tell me if the enthalpy is the state property that means it is different from one state to another right..??? So if Enthalpy of H2O at 30°, 1atm and Enthalpy at 32° ,1atm are different...?? Or same...?? And and does the energy of bond change with atmospheric property like temperatures, pressure ...???

My freaking savior

Best "Guru" ever....

Thank you, chemistry Jesus!!!!

I love this channel

Thank you professor Jesus

i don`t understande the example in the end of the video

01:13 Heat is NOT a FORM of energy. Heat is a PROCESS. Heat is the TRANSFER of energy due to a difference in temperature. Please read Peter Atkins: "Four Laws that drive the Universe", p.30.