Is Mass Always Conserved?

I show you how mass is always conserved, except when it isn't...

[TheActionLab]

When I talk about the buoyancy on the jar, I should have said that the buoyant force is the same in both cases, but when the gas is less dense, the jar weighs less with the same buoyant force up so it gets lighter. I made it more confusing than it needed to be:)

[spiderdude]

The apparent mass gain from burning burning metal was a big contender for the false assumption that mass could be changed and not conserved. It took very very careful measurements by Antoine Lavoisier to prove that in a closed system, mass is conserved. It required him to actually invent some of the most accurate measuring instruments that existed at the time to prove that it was true.

[danielrhouck]

Note that in both cases where the scale didn’t read a change, the jar was actually lighter at the end; energy escaped in the form of heat and light. Just, not *nearly* enough to notice.

[liambohl]

This was incredibly clear and concise. Well done!

[mixxairmonclair]

Just want to say that my 7 year old and I found your channel a while back. My kiddo was so fascinated with the first video we saw and we subscribed. This was several months ago.

[Kamel]

This is one of those satisfying times when I knew the answer before you even revealed it. Very clever way of demonstrating and explaining what's really happening here. Bravo, this is one of your best videos IMO which says a lot as you've had so many bangers.

[eideticex]

Thank you for demonstrating it in this way. Seen this demonstration as a child in science class and it stuck with my through my entire life. It was in this experiment that I learned how to give a short, concise explanation to people that weren't understanding the concept of spending mass to produce energy or the other way around. Sometimes in the overly simple explanation, the people that needed to hear it find a solution to whatever they were trying to solve.

[Ninja]

Thank you for the explanation. I knew about E=mc^2 but I never knew what it even meant. I always appreciate you explaining physics and chemistry concepts in a very understandable way

[DANGJOS]

3:20 I'm being a bit nitpicky here, but the buoyant force didn't actually increase here because there was no change in volume. The oxygen in the container simply relocated from the surrounding to the steel wool and so no mass/weight change.

[wiliam]

You are significantly underrated. Probably my favorite YouTube scientists due to your ability to teach and explain. You are gem😊

[Mooon_Light]

Well, I don't know much about radioactivity, but in our high school chemistry class, they taught us that a small amount of proton converts itself into energy to bind the nucleous together, that is why, the total mass of atom is slightly less than total mass of neutrons and protons combined in that atom.

[nick-leffler]

The fact you lighted something on fire thru glass was one of the coolest thing I've seen in a while.

[AA-bjbu]

I'm in my 20s and this just goes to show you've always something more to learn
Thank you for this video!!

[TheAdvertisement]

3:27 I was so confused on how that worked, thanks for the explanation!

[pigger]

This video could've saved me a lenghty discussion, when we had to explain this to a colleague a few days ago, because he didn't want to believe, that burning 6.3 pounds of gasoline produces 20 pounds of carbon dioxide. He got it eventually though.

[kentworch]

I'm happy to see that you actually understand Einstein's famous conversion formula. For an object with mass to travel at the full speed of light, it would have to be fully converted into energy. Otherwise there will be a difference between it's speed compared to C as well as time dilation to boot.

[mike.]

Simple yet interesting! And for a second there I thought you might have finally posted a video without a sponsor, but at least it was at the end.

[ErCanEverything]

You are genius, well good video my Friend.
Greetings from Bulgaria👋

[GoldRenard]

Oh wow, real life has such a beautiful shaders and particle system! Best engine ever 10/10.

[chinesefantasy]

Most metals combust when it comes in contact with air(oxygen), this is why fireworks work. But as soon as it's oxidizes the metal gets a protective layer that prevents it from getting on fire. And also why taking a sharp tool as a knife and scraping a piece of metal it will produce sparks.