In the video, the author discusses how chemical reactions occur in everyday life. They go over how to balance equations and what the different symbols mean.
00:00:00 The video discusses how everyday reactions in life, such as fruits changing color, inhalation of automobile fumes, and cheese and yogurt production, are the result of chemical reactions happening constantly. There are many questions that can be raised about these reactions, such as why some products change in color or form, or why we experience chemical reactions all the time. Some examples of chemical reactions are the formation of rust on iron, the production of smoke when a candle is burned, and the breaking down of sugar into glucose and fructose by the enzyme glucose-6-phosphate isomerase. When observing these reactions, it is often possible to determine if a chemical reaction has occurred by observing signs of energy release, such as light or heat.
00:05:00 The video discusses how gradual changes in color can be a sign of the presence of new substances, similar to how leaves change color due to the breakdown of pigments. In more complex reactions, more than one reactant can participate. The symbol that is most reactive with the arrow is written above the arrow to signify the reaction has occurred. Conditions under which a chemical reaction takes place are described with formulas and symbols, and reactions are divided into two main categories-reactants and products. Reactants are the substances that react, and are written to the left of the arrow, while products are the substances that are produced and are written to the right of the arrow. Simple reactions only involve one reactant and one product, but in some cases, multiple reactants and products can participate. The water droplet symbol (H2O) indicates that a physical process is taking place, while the upward-pointing arrow indicates that the substance that is produced is soluble. When a reaction releases energy, it is called an exothermic reaction. When a reaction absorbs energy, it is called an endothermic reaction. Before each substance is written, numerical coefficients are assigned to the reactants and products, which indicate the number of atoms or molecules of each substance that react. These
00:10:00 In this video, the author discusses how chemical reactions occur in everyday life. Carbon is adjusted in reactions involving products, with six hydrogen atoms to the left and two oxygen atoms to the right. In the reactants, there are three oxygen atoms, and in products there are eight. The adjustment is initiated with the element least common in our case, carbon, adding five molecules of diatomic carbon in the reactants counting the number of atoms of each type. We will see that the calculation produces the same result as the initial and final formulas. If we want to avoid writing many molecules, we add the total number of atoms before the diatomic carbon, yielding a 6 in front of the diatomic carbon. The oxygen atoms in the reactants are now equal to the oxygen atoms in the products, and the equation is now balanced. However, what happened to the number of atoms of oxygen in the reactants? In the reactants, there are now 13 atoms of oxygen, while in products there are only 8. This is because the atoms of oxygen involve themselves in all the compound substances in the equation, so it affects the values of the other substances. For the moment, we will leave this issue aside and focus on hydrogen. If we add a 6 to the molecule of water