
Why was atomic mass scale changed from Oxygen - 16 to Carbon
2015年1月7日 · The problem was that physics stuck to isotopically pure O-16 for their mass scale, and chemistry used "oxygen" (i.e., with some O-17 and O-18 present). There's 0.028% …
How do I calculate the molarity of the Na2CO3 solution?
Commented Oct 21, 2015 at 16:33. Add a comment | 2 Answers Sorted by: Reset to default 4 ...
How to calculate mass produced when a given gas is burned?
2017年6月21日 · The equation below represents combustion of methane ($\ce{CH4}$, $\pu{16.04 g/mol}$). Balance the equation, and calculate the mass of water ($\pu{18.02 g/mol}$) formed …
Which nuclei are NMR active? - Chemistry Stack Exchange
2017年5月4日 · Examples include $\ce{^{12}C}$, $\ce{^{16}O}$ and $\ce{^{32}S}$. All other nuclei are NMR active: Odd/Odd. Nuclei that contain an odd number of protons and an odd …
Which element has the highest binding energy per nucleon
2018年7月8日 · The graph of binding energy per nucleon (Hyperphysics) seems to peak at Iron-56. However, Wikipedia says that Nickel-62 has the highest binding energy per nucleon of any …
molecular orbital theory - Does the MS oxygen peak at m/z = 16 ...
2022年8月30日 · So the covalent binding energy expected for the proposed $\ce{O#O}$ triple bond in the gas phase would be insufficient to overcome the repulsion between two positive …
atoms - Are atomic mass unit (amu), unified mass unit (u) and …
2020年7月6日 · Chemists choose to define the amu as 1/16 of the average mass of an oxygen atom as found in nature; that is, the average of the masses of the known isotopes, weighted …
kinetics - If all molecules have basically the same KE at a given ...
2021年4月21日 · The simplest and most direct explanation is that isotopically heavier molecules have higher boiling points. Regular water (R) boils at 100.0 $^o$ C. Heavy water (H) boils at …
mole - amu and g/mol relation - Chemistry Stack Exchange
2014年6月20日 · $\begingroup$ @Martin that is a good point, but I think that for the most part 'amu' is understood to be the unified atomic mass unit based on carbon-12, not oxygen-16. I at …
What is the significance of 273.16 K? - Chemistry Stack Exchange
2018年2月20日 · For water, the temperature of the triple point (273.16 K) is remarkably close to its freezing point at atmospheric pressure (273.15 K). Because 0 °C was originally defined as …