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Docscientist
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Atomic mass,molecular mass and formula mass: how are they different and how are they used differently ?
Docscientist said:Atomic mass,molecular mass and formula mass:
The biggest problem is I don't even understand why atomic mass should be one twelfth the mass of one carbon 12 isotope.I know it's a relative way of finding the masses of other elements.I also know that it was chosen because it was a whole number (carbon 12 isotope has 12g of mass) but then practically how are we able to find the atomic mass of other elements ? Why do we do it that way ?drvrm said:An atomic mass unit (symbolized AMU or amu) is defined as precisely 1/12 the mass of an atom of carbon-12. The carbon-12 (C-12) atom has six protons and six neutrons in its nucleus.
Docscientist said:And how do we find the atomic mass of other elements then ?
Docscientist said:I mean I amu is one twelfth the mass of one carbon 12 isotope but HOW ?
Borek said:Because we defined it to be so, by choosing - arbitrarily - 12.
We could as well make it any other number, 5 or 42. These would be much less convenient to work with, but they are perfectly correct choices as well.
If we use mass spectrometry,we can find weight of all elements in terms of grams.If that is true why do we use "amu" as it's unit? Why can't it be in grams ? And if 1 amu is one twelfth the mass of one carbon twelve isotope,then how do we find the masses of other elements after weighing them using mass spectrometry in terms of "amu," or "u"?Drakkith said:See if this link helps: https://www.quora.com/Why-is-calculation-of-molecular-mass-based-on-carbon-12-and-not-hydrogen-1
I believe mass spectrometry is commonly used.
Docscientist said:If we use mass spectrometry,we can find weight of all elements in terms of grams.If that is true why do we use "amu" as it's unit? Why can't it be in grams ?
Docscientist said:And if 1 amu is one twelfth the mass of one carbon twelve isotope,then how do we find the masses of other elements after weighing them using mass spectrometry in terms of "amu," or "u"?
The basic difference between a scientist and a non-scientist is their approach to understanding the world. Scientists use the scientific method to systematically gather evidence and test hypotheses, while non-scientists may rely on personal beliefs or opinions without following a structured approach.
A hypothesis is an educated guess or prediction about a phenomenon that can be tested through experimentation. A theory, on the other hand, is a well-supported and widely accepted explanation for a natural phenomenon that has been rigorously tested and confirmed through multiple experiments.
Qualitative data is descriptive in nature and is based on observations or opinions. It is often used to explore and understand complex phenomena. Quantitative data, on the other hand, is numerical in nature and is measured using standardized methods. It is used to quantify and analyze data statistically.
A control group is a group in an experiment that is not exposed to the independent variable, while an experimental group is exposed to the independent variable. The purpose of a control group is to provide a baseline for comparison and to ensure that any changes observed in the experimental group are due to the independent variable and not other factors.
The dependent variable is the outcome or result that is being measured in an experiment, while the independent variable is the factor that is being manipulated or changed by the researcher. The dependent variable is expected to change in response to the independent variable, and it is used to test the hypothesis of the experiment.