Endothermic vs. Exothermic 4/30

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A chemical reaction can either be Endothermic or Exothermic. This means that the reaction can either absorb energy or release energy. An Endothermic reaction is a chemical reaction in which the solution absorbs energy from its surroundings. In contrast, the opposite of an Endothermic reaction is an Exothermic reaction. An Exothermic reaction is when the solution of a chemical reaction releases energy. This energy that is either absorbed or released is usually, but not always, in the form of heat. Since an Endothermic reaction absorbs heat, the products will have more potential energy than the reactants. This is because the reactants require more energy in order to complete the chemical reaction. In a Exothermic reaction, the products will have less potential energy than the reactants. The reactants of an Exothermic reaction have to release energy in order to complete the chemical reaction. You may be asking, where does the absorbed energy come from in an Endothermic reaction and where does the released energy go in a Exothermic reaction? The simple answer is the surrounding environment. In an Endothermic reaction, the energy comes from the surrounding environment of the chemical reaction. In an Exothermic reaction, the energy is released into the surrounding environment of the chemical reaction. An easy way to tell the difference between these reactions is by measuring the temperature. Since the energy usually comes in the form of heat, the temperature of a chemical reaction will change depending if it is Endothermic or Exothermic. In an Endothermic reaction, the temperature will decrease and the product will be a lower temperature than the reactants. In an Exothermic reaction, the temperature will increase and the product will be a higher temperature than the reactants.

S&EP - SP7: Engaging in argument from evidence

I used evidence to defend my explanation. I answered a worksheet in class about Endothermic and Exothermic reactions providing the examples and models on a website that was given to my classmates and I to use, as evidence. I formulated evidence based on solid data when I stated that the products of an Endothermic reaction is colder or a lower temperature than the reactants of the chemical reaction using the fact that energy (usually in the form of heat) from the surrounding environment is absorbed into the reaction and trapped inside the bonds of the molecules in an Endothermic reaction, making the surrounding environment colder, as evidence. I examined my own understanding in light of the evidence. I used to think that the temperature of the products in an Exothermic reaction would be cooler and at a lower temperature than the reactants because the heat energy was being released from the reactants, but because of learning that the energy is released into the surrounding environment of the chemical reaction, now I think that releasing the heat energy rises the temperature of the chemical reaction. I collaborated with my peers in searching for the best explanation. I did some research on Endothermic and Exothermic reactions and how they occur which I discussed with my class and table group. Together we figured out that an Endothermic reaction absorbs energy and an Exothermic reaction releases energy.

XCC: Cause and Effect

The cause and effect relationship that occurs in Endothermic and Exothermic reactions is between the reactants and products of the chemical reaction. The amount of potential energy that is in the product depends if the chemical reaction is an Endothermic reaction or Exothermic reaction. If the chemical reaction is an Endothermic reaction, the product will have more potential energy than the reactants. This is because the reactants of the chemical reaction absorb energy from the surrounding environment of the chemical reaction in order to break the bonds. If the reaction is an Exothermic reaction, the product will have less potential energy than the reactants. This is because the reactants of the chemical reaction release energy into the surrounding environment of the chemical reaction in order to form new bonds. In addition, the temperature of the product in the chemical reaction depends if the reaction is Endothermic or Exothermic as well. If the chemical reaction is an Endothermic reaction, the product is colder and at a lower temperature than the reactants. The temperature of the chemical reaction drops because the reactants absorb heat energy from the surrounding environment, making the surrounding environment of the chemical reaction colder. If the chemical reaction is an Exothermic reaction, the product is warmer and at a higher temperature than the reactants. The temperature of the chemical reaction rises because the reactants release heat energy into the surrounding environment, making the surrounding environment of the chemical reaction warmer.

Chemical Reactions 4/9

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A chemical reaction is when two or more substances meet and are converted into one or more different substances. The substances that are usually used in a chemical reaction are normally elements or molecules. An element is a substance located on the periodic table that can't be chemically introverted or broken down into simpler substances. Each element is made up of only one type of atom and are the primary constituents of matter. Whereas a molecule is a group of atoms bonded together. There are two primary bonds that connect these atoms together. One type of bond is called an ionic bond. An ionic bond is the complete transfer of electrons between atoms. This type of bond generates two oppositely charged ions, the attraction between the opposite charges is what holds the bond together. Another type of bond is called a covalent bond. This bond occurs when atoms that are bonded share electrons. In a chemical reaction, bonds between atoms are broken and created to form new molecules. More specifically, the atoms are rearranged together and new bonds are created between these atoms. Chemical reactions are represented by chemical equations. A chemical equation is the symbolic representation of a chemical reaction in the form of symbols and formulas. There are three parts to a chemical equation, the reactants, the yield, and the product. The reactants are all of the elements and molecules on the left side of the equation. The product are all of the molecules on the right side of the equation. The yield is the arrow that separates the reactants and the product. Chemical equations are balanced to show the same number of atoms of each element on each side of the equation. This means that both the reactants and product have the same number of atoms of each element throughout the chemical reaction. This happens because of the Law of Conservation Mass; which is that the atoms are balanced on each side of a chemical equation. 

S&EP - SP7: Engaging in argument from evidence

I used evidence to defend my explanation. I filled out a couple of online document worksheets about ionic bonding and covalent bonding and a couple of worksheets about counting atoms, the Law of Conservation Mass, and about a chemical reaction we did in class. I filled out the majority of these worksheets providing the slideshow presentations that my teacher explained to my class as evidence. However, for the worksheet about the chemical reaction we performed in class, I provided the experiment as evidence. I formulated evidence based on solid data when I stated that the amount of atoms of each element stays the same throughout a chemical reaction an that they are just rearranged into new molecules, using the Law of Conservation Mass as evidence. I examined my own understanding in light of the evidence. I used to think that only the same amount of atoms were balanced on each side of a chemical equation and that it didn't matter the amount of atoms of each element, but because of learning more deeply about the Law of Conservation Mass, now I think that the specific amount of atoms of each element stay the same on both sides of the equation. For example, if there were four hydrogen atoms and two oxygen atoms as reactants, there would still be four hydrogen atoms and two oxygen atoms as a product. However, the atoms would be rearranged differently into new molecules. I collaborated with my peers in searching for the best explanation. I did some research on chemical reactions and even performed an experiment of my own which I discussed with my class. Together we figured out the molecular arrangement of atoms throughout a chemical reaction.

XCC: Patterns

The pattern that occurs in the a chemical reaction relates to the Law of Conservation of Mass. The Law of Conservation Mass is the theory that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations. According to the Law of Conservation of Mass, the mass of the products in a chemical reaction must equal the mass of the reactants. Simply, the Law of Conservation of Mass states that the amount of matter stays the same on both sides of a chemical equation throughout a chemical reaction. Meaning that the number of atoms of each element in a chemical equation is the same amount in the product as it is in the reactants. So the pattern that I noticed in chemical reactions is that the amount of different types of atoms always stays the same before and after the chemical reaction. For example, in the chemical reaction with baking soda (sodium bicarbonate) and vinegar (acetic acid), the reactants are C2H4O2 + NaHCO3. For this part of the equation, there are three carbon atoms, five hydrogen atoms, five oxygen atoms, and one sodium atom. The product of this chemical reaction is sodium acetate, water, and carbon dioxide. The formula for the products is NaC2H3O2 + H2O + CO2. As you can see, the product includes three carbon atoms, five hydrogen atoms, five oxygen atoms, and finally one sodium atom. There are exactly the same amount of atoms of each element in the product as there were in the reactants.