In general, the more chemicals a battery has that can change into other chemicals, the longer it lasts, and this is partly what explains why alkaline batteries have a slight chemical advantage over their non-alkaline counterparts.’’ (education.com). Because of this, the alkaline batteries lasted longer than the non-alkaline batteries. The batteries chosen for this experiment are also alkaline batteries so it was already a good idea to use these types of batteries if they last longer than non-alkaline
The Lead Acetate Test is a specific test in indicating the presence of sulfur in the protein chain. This test only shows a positive result in cysteine and cystine, the only types of protein containing sulfur. In the experiment, the reagent used was lead acetate (Pb(OAc)2) in NaOH. As explained in Milio and Loffredo (n.d.), boiling of cysteine and sodium hydroxide (NaOH) in a water bath converts the sulfur in the protein into sodium sulfate (NaS), causing the precipitation of lead from the solution as observed with the presence of black precipitate once the reaction occurred. The presence of the black precipitate indicates that sulfide and not sulfate, which gives off a brown color, was present in the reaction.
α-Fe in α-FePO4 has a strength of 280 N/mm and also a hardness of approximately 80 Brinell. In pure iron, α-Fe is relatively stable when the temperature is below 1,670 °F. A very minimal amount of carbon can be dissolved in α- Fe and the maximum solubility is about 0.02 wt% at 1,333 °F and 0.005% carbon at 32 °F. The carbon is able to dissolve in the iron interstitially, with the carbon atoms being about twice the diameter of the interstitial "holes" and each carbon atom is surrounded by a strong local strain field. Thus, the resulting enthalpy of mixing is positive, which is unfavourable, but the contribution of entropy to the free energy of solution stabilises the structure for low carbon
In addition, lead produces renal neoplasms, interstitial fibrosis and progressive nephron loss, azotaemia and renal failure. Chronic lead exposure is also implicated in the development of saturnine gout and hypertension. The metal interacts with renal membranes and enzymes and disrupts energy production, calcium metabolism, glucose homeostasis, ion transport processes and the renin-angiotensin system. 32,29 Effect of lead on reproductive system: Infertility is a reproductive health problem worldwide which affects many couples especially in developing countries. Lead is ubiquitous and persistent heavy metal which has detrimental effects on almost all the major organs.33 Male and female reproductive systems are one of the major target sites of lead induced toxicities.34 Effect on Male reproductive
Carbon dioxide and water in the solution were also clear. Once the solution was completely titrated, Mn7+ ions remained unreduced and changed the color of the solution to pink. The KMnO4 was added to each solution until the oxalate solution reached the end point and changed to an extremely light pink color. The change in volume in the burette of the potassium permanganate recorded in all three trials was used to calculate the moles of oxalate in the 0.100-gram compound, giving the percent composition of the compound. The three trials reacted 27.95 mL, 26.61 mL, and 25.74 mL of potassium permanganate to determine 55.7%, 53.0%, and 51.3% respectively of oxalate in the compound with a 53.3% average.
The nucleophilic attack pushes the carbonyl electrons onto the carbonyl oxygen, which forms a short-lived intermediate. The third step is where the oxyanion electrons reform the bond with the aromatic amino acid. Then the bond between the carboxyl-terminus of the amino acid and the n-terminus of the residue is cleaved and its electrons are used to take out the hydrogen of the nitrogen on the Histidine 57. The c-terminal side of the polypeptide is free to dissociate form the active site. Step four is basically just where water can now enter and bind to the active site through hydrogen bonding, which is between the hydrogen atoms of water and the Histidine-57 nitrogen.
Balanced Chemical Equation: Cu(OH)2 (s) + Heat —> CuO (s) + H2O (g) Reaction 4: when a sulphuric acid is added to the solution that contains copper (II) oxide, a double displacement reaction will occur. the copper (II) oxide will react with the sulphuric acid producing copper (II) sulfate and water. The copper and hydrogen gas replace each other. Balanced Chemical Equation: CuO (s) + H2SO4 (aq) —> CuSO4 (aq) + H2O (l) Reaction 5: when zinc is added to the copper (II) sulfate solution, a single displacement reaction will occur. The zinc will form a new compound with the sulfate, and the copper will stay as a metal.
The positive or partially positive atom is referred to as an electrophile. The whole molecule which the electrophile and the leaving group are part of is called the substrate. The most general form of the reaction is represented as the following: Nuc: + R-LG → R-Nuc + LG: The lone pair on the nucleophile would attack the (R-LG) substrate, forming a new bond with the (R) resulting in the (LG) leaving the substrate with a lone pair. The product formed after the nucleophilic attack is (R-Nuc). After the nucleophilic substitution, the nucleophile can be neutral or carry a negative charge while the substrate can be neutral or positively charged.
Lead (Pb) Is largely derived from the combustion of lead additives in motor fuels as well as lead smelting. Lead pollution from vehicle emissions is declining due to the introduction of unleaded fuels and reductions in lead levels in leaded fuel. Other atmospheric sources of lead include waste incineration and renovation of old houses (from leaded paint). Lead retards learning in children and the development of their nervous system; Lead affects almost every organ in the body, whether it is inhaled or ingested. Young children are particularly susceptible; Hydro-carbons (HC) - chemical compounds composed of Hydrogen and Carbon atoms Most fuel combustion processes result in the release of hydro carbons to the environment.
This was due to excess hydroxide ions (OH-) from sodium hydroxide (NaOH) had been added into oxalic acid (C2H2O4) and acetic acid (CH3COOH) cause the solution turned into dark pink instead of light pink. This also indicated that the solution had been over-titrated with sodium