Second phase of UNICAMP 2023 with commented correction of the CHEMISTRY questions from the entrance exam for the State University of Campinas. The commented resolution is about the 06 chemistry questions of the test according to what is published in the official COMVEST answer key. This is a test used in the areas of Biological Sciences/Health and also in Exact/Technological Sciences. ✔ ► 00:00 Topics covered - Introduction ✔ ➊Ⓔ 01:56 (Q15) (UNICAMP 2023 - 2nd Phase) Concrete has a high tendency to form cracks that reduce its useful life and increase replacement costs. The self-healing of conventional concrete is the filling of its cracks, which occurs from the hydration of calcium oxide present in the composition of the concrete itself. Hydration produces calcium hydroxide, which reacts with carbon dioxide present in the ambient atmosphere. Bioconcrete, a new product on the market, is characterized by the presence of bacteria whose negative charges on their surface attract positive metal ions that precipitate with anions from the concrete environment; this forms a slightly soluble solid, responsible for closing the cracks (figure on the side). ✔ ➋Ⓔ 18:39 (Q16) (UNICAMP 2023 - 2nd Phase) In a scientific article, the authors present figure A with the aim of summarizing the most important aspects of a study carried out. a) Based on figure A, indicate the purpose of the experiment, name the transformation process and describe how the experiment was conducted. Be sure to mention chemical aspects represented by the graphic elements in the figure. b) Figure B shows some results obtained in the aforementioned work. Considering the data presented, propose the pressure that should be chosen for production with a higher proportion of lighter hydrocarbons. Justify your choice. ✔ ➌Ⓔ 32:37 (Q17) (UNICAMP 2023 - 2nd Phase) Recently, consumers have noticed that several alternative milk-based products, such as dairy drinks, have appeared on supermarket shelves. An article recently published on a news portal asks: “Are these dairy drinks healthy?” The interviewee answers: “Whey can be consumed as milk without any problem, since it is similar to skim milk, but without fat”. The report also provides a series of information about the composition of milk, whey, and a dairy drink, as shown in Table 1. ✔ ➍Ⓔ 47:41 (Q18) (UNICAMP 2023 - 2nd Phase) The timeline on the side presents events that occurred worldwide with the common objective of trying to establish agreements between different countries to mitigate environmental problems - and some regulations (actions) adopted in Brazil (text boxes). ✔ ➎Ⓔ 1:05:18 (Q19) (UNICAMP 2023 - 2nd Phase) A study carried out in 2021 identified that the exchange of one of the amino acids in the Spark protein of the new coronavirus may be one of the factors that influences a higher contagion rate in one of its mutations. In the exchange, the amino acid asparagine (Asn) at position 501 is replaced by tyrosine (Tyr). This exchange causes the altered Spark protein chain (Y501) to interact with the protein chain of the receptor cells differently than the original protein chain (N501). The figure on the side illustrates part of the intermolecular interactions between the cell receptors and the original virus protein (N501) and the mutation protein (Y501). ✔ ❻Ⓔ 1:20:27 (Q20) (UNICAMP 2023 - 2nd Phase) Despite the protective benefits that the use of cosmetics and sunscreens brings to the skin, their presence is also connected to environmental and health problems. To avoid unnecessary reapplications of UV blockers, the permeability of the active ingredient in the skin must be relatively low. This permeability can be described quantitatively by the permeability coefficient, Kp (cm/s), which can be calculated from the molar mass M of the chemical and its partition coefficient Kow = [solute in octanol] / [solute in water]. The empirical relationship between these quantities is given by the equation: ✔ ► 1:43:46 INTERDISCIPLINARY Themes, Topics and Conclusion OF NATURAL SCIENCES • ✏️ Wind energy has been pointed out... Don't waste time ⌚ subscribe to the channel so you don't miss any content!❤ ► / @quimicapravaler Any questions about the subject of the class? Leave a comment! ---------------------------------- #químicapravaler #unicamp #comvest