On the Regularity of the Electron Configuration of Atoms in the Periodic Table

The current periodic table does not necessarily have a clear position for transition elements. Therefore, the purpose of this paper is to use the basic principle discovered by Mendeleev as it is and to create a periodic table with consistency for transition elements. By setting some hypotheses, it was found that transition elements also have regular periodicity, so we succeeded in clarifying the energy level of electrons in each orbit. In addition, by utilizing its periodicity, the electron configuration for each orbit was predicted for unknown elements. In this paper, we did not take the conventional idea of electron orbitals, that is, the idea of forming a hybrid orbital, but assumed a new orbital. Since the state in which electrons fit in orbits and stabilize is defined as an octet, this idea was used as the basic principle in this paper, but the hypothesis that "there are only three orbits in each shell" was established and verified. The calculation of the energy level of the electrons on the orbit became extremely easy, and the order of each orbit could be clarified. It was also found that the three-dimensional structure of the molecule may be visualized by paying attention to the valence electrons of the outermost shell of the element and the octet of the stability condition. Therefore, in this paper, by slightly expanding the structural formula of Kekulé, it became possible to easily determine whether or not the molecule synthesized by the bond between elements is stable. In addition, it has become possible to predict the three-dimensional structure of the molecule as well. Furthermore, not only will it be easier for students studying chemistry to understand complex chemical reactions, but it will also be useful for researchers in the development and research of new drugs.

Comparative Effectiveness of Virtual Laboratory Instructional Package in Teaching Chemistry in Private and Public Secondary Schools

The study investigated Comparative Effectiveness of Virtual Laboratory Instructional Package in Teaching Chemistry in Private and Public Secondary Schools in Ondo State, Nigeria. The purpose of the study was to compare the performance of students in chemistry in both private and public secondary schools in Ondo state using Virtual Laboratory Instructional Package. The study adopted the quasi-experimental pretest/posttest control group design. The sample for the study consisted of 183 senior secondary school two (SSSII) science students that were selected across the three senatorial districts of Ondo state using multistage sampling techniques. Two groups were involved in the study; the experimental group and the control group. The students in the experimental group were exposed to virtual laboratory instructional package while the control group was taught chemistry with the conventional method. One instrument; Chemistry Achievement Test was used to collect data for the study. The reliability of the instrument was ascertained through test-re-test method and the reliability index of 0.75 was obtained for the instrument. Hypotheses 1, 2 and 3 were tested with Analysis of Covariance (ANCOVA). However, Multiple Classifications Analysis (MCA) was used to identify the variable that contributed to the difference among groups. All the hypotheses were tested at 0.05 level of significance. The findings of the study showed that students exposed to Chemistry practical through virtual laboratory Instructional package in private secondary schools performed significantly better than their counterparts in public secondary schools. It was also found from the study that, gender has no effects on student’s performance in public secondary schools meanwhile; there was gender difference in the performance of students in private secondary schools in favour of female students. Based on the findings, it was recommended that Government at all levels should endeavour to provide information and communication facilities like computer based instructional package in schools to teach chemistry and such must be made accessible to all students, so as to promote interactive and individualized learning among secondary school students.

Naturally Occurring Exudates Gums as Ecofriendly Inhibitors for Mild Steel Corrosion in Acidic Medium

The corrosion inhibition potentials of gum exudates from Daniella oliveri (DO) and Commiphora Africana (CA) for the corrosion of mild steel in H2 SO4 have been studied using weight loss and thermometric methods at 303 and 333K. Results show that the exudates gum actually reduced the rates of corrosion of mild steel. Increase in the concentrations of the exudate’s gums increased their percentage inhibition efficiencies. Corrosion rate was found to increase with increase in temperature in the presence and absence of the gum exudates, though the corrosion rate was slower in the presence of the exudates gums. Both DO and CA exudates gums were found to obey Temkin and Langmuir adsorption models at all concentrations and temperatures studied. Physical adsorption mechanism was proposed from the adsorption parameters. Kinetic and thermodynamic parameters revealed that the adsorption process is spontaneous, exothermic and no significant difference was found between the inhibition efficiencies of DO and CA.

Extraction of Beta-Carotene as Natural Dyes from Cucumis Melo Via Soxhlet Extraction Method

Natural dyes are pronounced as an interesting alternative to fabricated dyes. Accordingly, the attractive demand to develop the extraction techniques of the best ingredients of solid and liquid for natural dyes colorants from fruits materials and their application in human life. Extraction is processed using solvents or using modern techniques like ultrasonication and microwave. In this respect, the extraction of natural colorant from Cucumis melo has been investigated as a model. Determination of the structure of active ingredients was performed conducted by UV spectroscopy and gravimetrical analysis. Through the analysis of the results, it will be confirmed that the dye extracted from Cucumis melo of intense color is beta-carotene, which is considered as one of the most colored dyes. Therefore, we recommend using such dyes in the industrial fields especially for coloring and decorating sweets.

Modification to a Formulation for Optimal Performance

The chemical composition of household chemicals used was identified in table 1. The bubbling power of the tablets in water was found to be due to the reaction between vitamin C and cream tartar with baking soda. The molar amounts of reactants were calculated for optimal performance, producing the greatest amount of bubbling per tablet.

Assessment of Chemistry Laboratory Equipment Availability and Practice: A Comparative Study Between Damot and Jiga Secondary Schools

The project was designed to compare the laboratory equipment availability (facilities) and status of practical work between Damot senior secondary school and Jiga senior secondary school and their performance with the standard (average test value). All chemistry teachers and 30 students from each secondary schools a total of 84 respondents were involved. Closed ended questionnaire were prepared and descriptive survey method was employed to describe and one sample t-test method was used to assess the degree of availability of facility and the status of implementation and independent t-test was used to compare the degree of availability of facility and the status of implementation. Total average equipment availability and total average laboratory practice (Mean=2.09, sd=0.29, t(83)=-12.53, p<0.05) is far from the test value (2.5). Average Laboratory equipment availability and laboratory practice in Damot high school is (Mean=2.31, SD= 0.221, n=43) had statistically significant difference from Jiga high school (Mean=1.87, SD=0.158, n=41), t(82) =10.611, p<0.05, Cohen’s d=2.32. From the analysis of Chemistry laboratory equipment availability and laboratory practice in both Damot secondary school and Jiga secondary school were found in very low level and much far less than the average availability of chemistry laboratory equipment and status of laboratory practice. From the data analysis average chemistry laboratory equipment availability and status of laboratory practice of Damot secondary school is better than that of Jiga secondary school.

Bio-Waste Curd Water as a Greener Protocol for the Synthesis of Biginelli Products at Ambient Temperature

A highly efficient, greener and reusable protocol has been developed for the Biginelli reaction. The biowaste curd water employed as a green solvent as well as catalyst for the synthesis of dihydropyrimidinones derivatives. The soluble organic acid (i.e. lactic acid) responsible for the acidity to curd water which adequately fulfills the purpose of acid catalyzed reaction, where three component coupling of aldehyde, urea and ethyl acetoacetate reacted together in the presence of curd water at a low temperature and yields classical dihydropyrimidinones derivatives. During the reaction, continuous product formation and isolation was observed. The product precipitate was separated by the successive method of filtration. This bio-waste water catalyzed method is highly retrievable and advantageous over the trend of high-temperature Bronsted acid/metal acid catalyzed reactions offering the product. Compared with the classical Biginelli reaction conditions, this new method has the advantage of good yields (76-82%) and short reaction time (2-3 hours)

Theory of Heat Transfer in Straight Round Pipes with Square and Triangular Turbulators Under High Reynolds Criteria

Objectives: To carry out mathematical modeling of the structure of vortex zones between periodic flow turbulators with a surface arrangement of triangular and square transverse profiles on the basis of multi-block computing technologies based on solutions of the Reynolds equations (closed by means of the Menter shear stress transfer model) and energy equations (on multi-scale intersecting structured grids) with high Reynolds criteria Re = 106 with an exhaustive analysis of the corresponding current lines. Method: The calculations were carried out on the basis of a theoretical method based on the solution of the Reynolds equations by the factorized finite-volume method, which are closed using the low-Reynolds model of the Menter shear stress transfer, and the energy equation on multi -scale intersecting structured grids (FCOM). Result: Mathematical simulations of the heat exchange process in straight and round pipes with turbulators with d / D = 0.95 ... 0.90 and t / D = 0.25 ... 1.00 square and triangular cross-sections at large Reynolds numbers (Re = 106) on a foundation with multi-block computing technologies, which are based on solutions of the Reynolds equations and energy equations in a finite-volume and factorized way. It is found that the relative intensification of heat transfer [(Nu / Nusm) | Re = 106] / [(Nu / Nusm) | Re = 105] in round pipes with square air turbulators for large Reynolds numbers (Re = 106), which may well be relevant in the channels used in heat exchangers, may be higher with a large-scale increment of hydraulic resistance than for slightly smaller numbers (Re = 105), for relatively high flow turbulators d / D = 0. 90 for the entire range under consideration for the parameter of the relative step between them t / D = 0.25 ... 1.00 a little more than 3%; for turbulators of triangular cross-section, similar indicators are approximately the same. For lower square turbulators with d / D = 0.95, this increase in relative heat transfer for large Reynolds numbers (Re = 106) compared to smaller numbers (Re = 105) does not exceed 6%; for triangular cross-section turbulators, similar indicators are slightly more than 4%. Conclusion: According to the results of calculations based on the developed model, it is possible to optimize the intensification of double turbulators, as well as to control the process of heat transfer intensification. It is shown that for higher square turbulators and at higher Reynolds numbers, a slight increase in the relative Nusselt number Nu / Nusm is accompanied by a significant increase in the relative hydraulic resistance due to the very significant influence of return currents, which can flow directly on the turbulator itself to the greater extent, the higher the Reynolds number; for triangular turbulators, the above trend persists and even deepens.

evelopment the Professional Competence of Students on the Continuous Natural Scientific Education in the Uzbekistan

The article summarizes the experience of teaching natural science disciplines for various areas of training of students in pre-university educational institutions. The purpose of the disciplines “Chemistry”, “Physics” and “Biology” is to form a holistic natural science worldview among students, which determines both the scope of tasks and the list of general cultural and general professional competencies being formed. The study revealed that in lyceums that implement continuing education in the “college-university” and “lyceum–university” systems, it is advisable to study general subjects of the natural science cycle at two levels: basic and advanced degrees. The study showed that in the course of general education natural science disciplines, it is advisable to allocate professionally significant information in a separate block (module).

Electrochemical Biosensor Based on Furosemide-Gold Nanoparticles for The Determination of Dopamine for Practical Applications

In this study, by taking the advantage of the facile & controlled synthesis of furosemide derived gold nanoparticles (Fr-AuNps) for rapid and sensitive amperometric determination of dopamine (DP). The one-step synthesis of FrAuNps was carried out at room temperature without the use of strong reducing agents. The synthesized Fr-AuNps were studied by UV-Vis spectroscopy, and a strong absorption band for gold nanoparticles was observed at 520 nm. Transmission electron micrographs (TEM) revealed the average particle size below 100 nm. HRTEM showed excellent crystalline features as prepared gold nanoparticles. The electrochemical behavior of gold nanoparticles was examined by cyclic voltammetry (CV) which demonstrated the enhanced electrocatalytic kinetics activity towards the oxidation of dopamine. The presented dopamine biosensor exhibited a linear response for the dopamine in the range of 0.25 to 7 µM. The calculated the detection limit found to be 18.3 nM and limit of quantification 61.5 nM respectively. The proposed dopamine biosensor was successfully employed for the quantification of trace amount of dopamine from human serum and the obtained results are very satisfactory.