Search results
Results from the WOW.Com Content Network
RNA folding problem: Is it possible to accurately predict the secondary, tertiary and quaternary structure of a polyribonucleic acid sequence based on its sequence and environment? Protein design : Is it possible to design highly active enzymes de novo for any desired reaction?
In chemistry, the empirical formula of a chemical compound is the simplest whole number ratio of atoms present in a compound. [1] A simple example of this concept is that the empirical formula of sulfur monoxide , or SO, is simply SO, as is the empirical formula of disulfur dioxide , S 2 O 2 .
However, the empirical formula for hexane is C 3 H 7. Likewise the empirical formula for hydrogen peroxide, H 2 O 2, is simply HO, expressing the 1:1 ratio of component elements. Formaldehyde and acetic acid have the same empirical formula, CH 2 O. This is also the molecular formula for formaldehyde, but acetic acid has double the number of atoms.
In quantum chemistry, Slater's rules provide numerical values for the effective nuclear charge in a many-electron atom. Each electron is said to experience less than the actual nuclear charge, because of shielding or screening by the other electrons.
The Eyring equation (occasionally also known as Eyring–Polanyi equation) is an equation used in chemical kinetics to describe changes in the rate of a chemical reaction against temperature. It was developed almost simultaneously in 1935 by Henry Eyring , Meredith Gwynne Evans and Michael Polanyi .
A compound's empirical formula is a very simple type of chemical formula. [27] It is the simplest integer ratio of the chemical elements that constitute it. [28] For example, water is always composed of a 2:1 ratio of hydrogen to oxygen atoms, and ethanol (ethyl alcohol) is always composed of carbon, hydrogen, and oxygen in a 2:6:1 ratio.
In chemistry, a formula unit is the smallest unit of a non-molecular substance, such as an ionic compound, covalent network solid, or metal. [1] [2] It can also refer to the chemical formula for that unit. Those structures do not consist of discrete molecules, and so for them, the term formula unit is used.
A molecular formula enumerates the number of atoms to reflect those in the molecule, so that the molecular formula for glucose is C 6 H 12 O 6 rather than the glucose empirical formula, which is CH 2 O. Except for the very simple substances, molecular chemical formulas generally lack needed structural information, and might even be ambiguous in ...