National educational content standards are supposed to provide an equality of the school education for the different types of schools. The present study aims at the evaluation of the 10th grade student achievements of the State educational requirements in Chemistry and Environment school subject according...
What is the general formula of alkynes? CnH2n−2CnH2n-2 CnH2n+2CnH2n+2 CnH2n+1CnH2n+1 CnH2n−1CnH2n-1 Grade 10Organic Chemistry Which statement correctly describes ethane and butane? They have only single bonds. They have the same number of hydrogen atoms. ...
Using the proposed method, the potential reduction in cost from the use of battery-grade graphite is at least an order of magnitude, with considerable better results achieved in terms of capacity and intrinsic structural benefits of the substrate, which include direct con-tact of the active ...
(Chemistry) the branch of chemistry concerned with the way in which the physical properties of substances depend on and influence their chemical structure, properties, and reactions Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998,...
Hunan Institute of Geological Survey, Changsha 410116, Hunan, China Fund Project: This research is financially supported by the China Geological Survey (Grant DD20160032-17) and the Fund for Young Scholars of Hunan Province(Grant 2018JJ3269) ...
Friction determines whether liquid droplets slide off a solid surface or stick to it. Surface heterogeneity is generally acknowledged as the major cause of increased contact angle hysteresis and contact line friction of droplets. Here we challenge this l
This study presents the results of an analysis of high school chemistry textbooks and teacher-generated questions about gas laws. The materials that were analyzed consisted of 456 questions about gas laws found in seven grade 10 chemistry textbooks and 264 teacher-generated examination questions prepare...
of chemistry education shows that a focus of attention for the macro-submicro interplay problem is put in the relations between observations and inferences; we examine such relations with the aid of ideas from the philosophy of science and the specific philosophy of chemistry. We propose a model...
We propose explicit and implicit approaches for the teaching of acid-base chemistry based on research into the history and nature of science (NoS). To support these instructional proposals, we identify four rationales for students to understand acid-base processes: daily life, socio-scientific, curr...
The sample was extracted three times by 4, 2, and 2 mL of dichloromethane HPLC Grade during 5 min at 700 rpm. The resulting organic extracts were dried with anhydrous sodium sulfate (Na2SO4) and concentrated to 0.25 mL under nitrogen gentle flow. An Agilent 7890 A gas ...