• the type of disinfectant used ,say for considering case of disinfection by chlorine dioxide (ClO2) substantial amount of chlorite (ClO2 -) is formed which acts as a precursor or product. (Bull ,1982) • the disinfection dose, • the residual disinfection involved, • nature and conditions of disinfection • temperature, and pH, • reaction time, • nature of source water • the constituents of water (organic as well as inorganic ), and • most importantly the concentrations and properties of naturally present organic matter (NOM)in the water. Thus ,the amount of organic precursors including the algal load in the drinking water to be treated , water temperature and pH, the amount and type of chemical disinfectants, and the stage in the process
As can be seen in Fig.4, a higher ratio of p-xylene to methyl acetate can produce higher selectivity of acetic acid against water. It showed the positive influence of the high amounts of p-xylene on the selectivity. This is coherent with the idea that adding p-xylene into methyl acetate as a mixed solvent could lead to enhance the values of capacity of extraction and selectivity of acetic acid against water. This result showed p-xylene is powerful enough to be considered as the feasible solvent when mixed with methyl acetate. Likewise, the use of p-xylene
What is the specific mechanism responsible for producing this effect (Be specific)? (6 marks) The antidiuretic hormone (ADH) is synthesized by neurons located in the hypothalamus and are stored in and secreted by the posterior pituitary gland (Silverthorn et al., 2013). The high osmolarity of a dehydrated person is the primary stimulus for the secretion of ADH (Saladin, 2004). This hormone acts on the collecting duct of the nephron (Silverthorn et al., 2013). ADH increases and water reabsorption and decreases osmolarity of renal filtrate (reduces urine output) by two mechanisms.
It is faster due to the filter funnels surface area. Results/Observations Experimental data resulted as expected because it was found that on experiment one, Benzoic Acid could recrystallize with a better recovery percentage than the solvent pair in experiment two. The mass recovered in experiment one was 0.048g while experiment two had a mass recovery of 0.045g. Solvent(s) Used Mass of “Crude” (g) Mass of Recovered (g) Amount of Solvent Used (mL) Percent Recovered (%) Experiment One Water (H2O) .051 .048 1.0 94.1 Experiment Two Methanol (MeOH) And Water (H2O) .049 .045 Methanol – 1.5 Water – 0.5 92 Conclusion Both experiments were of fair solubility, but in the case of recrystallization of Benzoic Acid, Water was the best solvent to recrystallize acid the most. Experimental data determined that there was a difference of .003g between using the single solvent in comparison to the paired solvent.
It is a strong mineral acid with many industrial uses. Hydrochloric acid is naturally found in the gastric juices of the stomach. The most important role of hydrochloric acid is to break down the foods and cause the release of enzymes that further
When pH is high which means more OH⁻, then aluminum ions will react with hydroxide ions to form aluminum hydroxide. Phosphate ions are acting as a natural buffer. If the equipment is not washed with acid, it would cause an error. This is because the phosphorus analyzing is dealing with low concentration of phosphorus and it is easily contaminated by detergent and other chemicals and it has to be washed by using an acid and also it has to be rinsed with distilled water once it is rinsed with acid. Also refer to section 4 (discussion).
- Medicinal Chemistry - Question No. 3. Define the Hammett Constant and the hydrophobic (Hansch) substituent constant. Comment on how inductive and mesomeric polar effects are treated in substituted aromatic systems. A quantitative structure-activity relationship (QSAR) is an equation which correlates measurable or calculable physical or molecular properties to some specific biological activity.
The extended model of Traüble –Haines-Liebowitz. Cholesterol inhibits the water permeability of phospholipid membranes reducing it in nearly one order of magnitude at 1:4 cholesterol:phospholipid ratio. This is concomitant with a reduction in the lateral mobility of the lipids. According to the Haines-Liebowitz-Traüble model, permeability is connected to lateral diffusion . In FTIR spectroscopy, there is a reduction of the value indicating that the connected populations of CH2 increases with the cholesterol ratio, which is totally compatible with the water permeability decrease via the reduction of kinks .
Enthalpy of neutralization The purpose of this experiment is to determine the enthalpy change for the reaction between aqueous sodium hydroxide (NaOH) and aqueous hydrochloric acid (HCl). Introduction A neutralization reaction is a chemical reaction where a base and an acid react with each other. The products will always be water and a salt. The balanced reaction equation for this experiment is the reaction below (Enthalpy of neutralization, 2018). 〖NaOH〗_((aq))+〖HCl〗_((aq))→〖NaCl〗_((aq))+H_2 O_((l)) In aqueous solutions the substances that are involved will experience dissociation, which changes the ionization state of the substances (Neutralization, 2018).
Conclusion It was clearly observed that the decrease in the concentration of hydrogen peroxide lead to increase in the reaction time and also decrease in the rate of the reaction. Also the decrease on the concentration decreases the rate of the reaction. The two graphs were straight line graphs with positive slopes. So effective collision for a chemical reaction depends directly on the concentration of the reagent, that is, the crowdedness of the reacting molecules which increases reaction time and vice versa. References