Comment on Banana for scale
sumsinj@lemmy.world 1 day agoYou know that water being exactly 1kg and 1l is specific to one pressure and temperature combination?
Comment on Banana for scale
sumsinj@lemmy.world 1 day agoYou know that water being exactly 1kg and 1l is specific to one pressure and temperature combination?
BitUnWise@programming.dev 1 day ago
Mole is a number of particles, not a volume. A mole of hydrogen-1 will always have the same mass regardless of temperature or pressure
Eheran@lemmy.world 17 hours ago
The point is that you do not have that precision. But it absolutely is good enough for pretty much everything. A 0.8 % error is often well below measurement error. Like in any mass balance in a chemical system, say a refinery or whatever. You can ignore argon and all other gases except N2 and O2 in air for the same reason in almost every application.
But even if we apply the same logic, 1.008 is “incorrec” too, it is 1.00794.
And that is incorrect too, not because of higher precision, but because of binding energy. Two separate hydrogen atoms (2 H) have slightly more mass than one hydrogen molecule (H₂) because forming the H–H chemical bond releases energy, reducing the system’s mass according via
BitUnWise@programming.dev 12 hours ago
This post was about definitions in the metric system, so while 1 mole of hydrogen being 1 gram is pretty close, it isn’t and isn’t defined to be
BreadOven@lemmy.world 14 hours ago
6.022x10^23 particles if I remember correctly.
nightlily@leminal.space 1 hour ago
Avogardo‘s number (Not Avocado‘s number as I wrote in my high school chemistry exam)