Over the past few decades, material scientists and chemists have been working on designing increasingly sophisticated materials for a wide range of technological and scientific applications. These materials include synthetic ...
(PhysOrg.com) -- "Although the orb web of a spider is a lightweight structure, it seems to be a highly optimized structure, presumably as a result of evolution from the Jurassic period or earlier," explain physicists Yuko ...
Astronomers have performed a comprehensive chemical study of a Galactic globular cluster known as Terzan 6. Results of the study, presented in a research paper published June 11 on the pre-print server arXiv, could advance ...
The first generation of stars transformed the universe. Inside their cores, simple hydrogen and helium fused into a rainbow of elements. When these stars died, they exploded and sent these new elements across the universe. ...
Astronomy
Mar 20, 2024
1
209
Italian astronomers have performed high-resolution spectroscopic observations of a young open cluster known as Messier 39. Results of the observational campaign, presented in a paper published Dec. 14 on the pre-print server ...
Janus adhesive hydrogels hold promising applications across health care fields. Nevertheless, a simple method to synthesize the material had yet to be bioengineered in the lab.
Using the Caucasian Mountain Observatory (CMO), Russian astronomers have observed a peculiar infrared source designated IRAS 07253-2001. Results of the observational campaign, published July 20 on the preprint server arXiv, ...
Scientists have transformed single-cell algae into functional perovskite materials. The team, led by scientists at the B CUBE–Center for Molecular Bioengineering at TU Dresden, converted mineral shells of algae into lead ...
Biochemistry
Mar 13, 2023
1
436
The Donnan electric potential arises from an imbalance of charges at the interface of a charged membrane and a liquid, and for more than a century it has stubbornly eluded direct measurement. Many researchers have even written ...
General Physics
Dec 19, 2022
0
232
Scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory have developed a new way to guide the self-assembly of a wide range of novel nanoscale structures using simple polymers as starting materials. ...
Nanomaterials
Nov 18, 2022
0
365
In chemistry, the empirical formula of a chemical compound is a simple expression of the relative numbers of each type of atom in it, or the simplest whole number ratio of atoms of each element present in a compound. An empirical formula makes no reference to isomerism, structure, or absolute number of atoms. The empirical formula is used as standard for most ionic compounds, such as CaCl2, and for macromolecules, such as SiO2. The term empirical refers to the process of elemental analysis, a technique of analytical chemistry used to determine the relative amounts of each element in a chemical compound.
In contrast, the molecular formula identifies a numbers of each type of atom in a molecule, and the structural formula also shows the structure of the molecule.
For example, the chemical compound n-hexane has the structural formula CH3CH2CH2CH2CH2CH3, which shows that it has 6 carbon atoms arranged in a straight chain, and 14 hydrogen atoms. Hexane's molecular formula is C6H14, and its empirical formula is C3H7, showing a C:H ratio of 3:7. Different compounds can have the same empirical formula. For example, glucose, formaldehyde and acetic acid have the same empirical formula, CH2O. This is the actual chemical formula for formaldehyde, but acetic acid has double the number of atoms and glucose has six times the number of atoms.
This text uses material from Wikipedia, licensed under CC BY-SA
