Substrate concentration basically means the amount used for the substrate. The substrate in our experiment was 0.1% hydrogen peroxide. The 0.1% is the concentration amount. Just like temperature and pH, substrate concentration can speed the reaction only up to a certain limit. When we mixed pH 3 enzyme tube with substrate tube, we used 0.3 mL of hydrogen peroxide, but if we were to increase the amount, then the experiment would have been faster.
The second reason is that the nonmetals have smaller atomic sizes making it easy to attract electrons but difficult to pull them away. 12. A lot of energy is required to break a strong intermolecular bond. This is because atoms in certain compounds have very strong bonds that require energy to break. This explains why some compounds have higher boiling points than others.
Therefore, they can undergo electrophilic substitution reaction and the attacking species, in this case, will be an electrophile. The +M effect will result in the concentration of electron density at ortho −and para −positions. However, electrophilic substitution reactions with respect to the haloarene reactions are slow in comparison to benzene reactions. This is because the halogen group present in haloarenes are deactivating because of the –I effect. Hence, electrons are withdrawn from the benzene ring.
After the nucleophilic substitution, the nucleophile can be neutral or carry a negative charge while the substrate can be neutral or positively charged. In this lab, a primary alcohol is converted to an alkyl bromide and a benzyl chloride into an ester using the SN2 reaction. Factors affecting the rates of both SN1 and SN2 reactions will also be investigated. In 1935, two scientists by the names of Sir Christopher Ignod and Edward D. Hughes, studied nucleophilic reactions of alkyl halides. Ignod first grouped organic reactions
Depending on where the nitronium group or the alpha complexes of the reaction is on the ring, determines whether the product will be meta, para or ortho. The energy required for ortho and para positions are much lower than if the atom is in a meta position. The reaction below illustrates the different products that can be formed: The bromine atom that is present in the reaction is an ortho-para director because it favors the formation of the product to be either ortho or para instead of being in a meta position. In addition, the presence of an electron withdrawing group or electron releasing group aids in determining whether the products will be in a meta, ortho or para position. The presence of an electron releasing group, in this reaction it is the bromine atom, the nitronium group will be attached in wither the ortho or para position.
In contrast to benzene, the electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. For this reason, pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy) Production[edit] Chichibabin synthesis In its general form, the reaction can be described as a condensation reaction of aldehydes, ketones, α,β-unsaturated carbonyl compounds, or any combination of the above, in ammonia or ammonia derivatives. [66] In particular, unsubstituted pyridine is produced from formaldehyde and acetaldehyde Formation of acrolein from acetaldehyde and
Grignard reagent is added to get an alcohol which may be secondary alcohol or tertilly alcohol and it also may form a primary alcohol, if an organometallic halide is added to formaldehyde. We can also get alkanes from this reagent by adding it to water, this type of reactions happens by the expulsion of weak acid from it's salt and using another strong acid. In general, in Grignard reagent it's be the addition of an organomagnesium halide to aldehyde or ketone . 1- Grignard reagents react with oxygen of the air or moisture but the air must be replaced with an inert gas like, argon or nitrogen because these reagents are so sensitive to moisture and oxygen. Properties of Grignard reagents : 2- Grignard reagents dissolve rabidly in two types of ethers, alicyclic ether and aliphatic ether and they also dissolve in other solvents.
The arrangement of electrons in an atom is known as its electronic configuration. How does an electronic configuration look like? It is commonly believed that the electrons move around the nucleus randomly in a three-dimensional pattern defined by their energy level. In the case of Lithium the three electrons are separated into two energy levels. 2 electrons are in the lower level, called 1s-orbital, and 1 electron is in the 2s-orbital.
The chlorine atoms that are replaced by hydrogen atoms causes a higher presence and both are covalent bondings with strong intermolecular forces. The double bondings (Or triple bondings) in hydrocarbon tends to be stronger, but the chemical is flammable. Fluorocarbons are not flammable and are also polar covalent bondings, making them stable to ultraviolet radiation and prevents them from catalysing ozone depletion. Hydrochlorofluorocarbons (HCFCs), one of the alternatives that contains C-Cl bondings have most of its molecules dismantled in the lower atmosphere before reaching the stratospheric ozone layer. Another chemical, Hydrofluorocarbons (HFCs), having no chlorine atoms which does not bring harm to the ozone layer is considered the best alternative since they are not flammable, such as CF3CH2F,1,1,12 tetrafluoroethane.
However, the almost linear promoting effects of DME addition were found in propane and n-butane ignition delays [23, 25]. This is mainly due to that the reactivity of methane is much lower relative to that of DME. Therefore, even with a small amount of DME addition, the ignition was strongly promoted by the decomposition of DME accompanied by the rapid build-up of free radicals, thus lead to the nonlinear promoting effect on methane ignition [21, 22]. However, for the higher order alkanes such as propane and butane, the reactivity of which are higher and the ignition delay times are much shorter relative to methane. Moreover, in the high temperature oxidation of methane, the rate of the governing reaction CH4 + O2 CH3 + HO2 is much slower than of the similar reactions of the higher order alkanes [22].