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Student and teacher narratives on chemistry

Teacher :     All students, don’t you understand about the electrolysis cell matter we have been learned today? (All the students were silent) Teacher :     Why are you just silent? I assume to have understood. Okay then we will test your understanding, if nobody wants to ask. (The student is restless, until in the end, the student asks a question). Student 1:   Miss (raise his hand) I still do not quite understand. Teacher :     Good, at least you will be stalling the test time for a while. What do you not understand about the material of electrolysis cell this time? Student1 :   I still find it difficult to understand the reactions that occur in Anode and Cathode when using a not-inert electrode? Teacher :     Okay, so here we go. The electrolysis cell is the decomposition of an electrode by the presence of an electric current. When an electrolyte is electrolyzed, the electron breaks down into catio...

Cause and effect of chemical reactions

Factors of chemical reaction Can be caused by several things: A. Happened by burning B. Mixing of substances C. Occurred due to electricity A.     Chemical reactions Occur due to burning For burning without external ignition, see spontaneous combustion. For vehicle engines, see internal combustion engine. Fire generated from combustion fuel Burning 'is a sequence of chemical reactions between a fuel and an oxidant, accompanied by the occasional heat production accompanied by light in the form of a fluorescent or flame. In a complete combustion reaction, a compound reacts with an oxidizing agent, and the product is a compound of each element in the fuel with the oxidizing agent. Example: The standard reaction enthalpy for combustion of methane at 298.15 K and 1 atm is -802 kJ / mol. Another example: A simpler example can be observed in combustion of hydrogen and oxygen, which is a ...

Chemistry Vocabulary

·          Element : If all the atoms in a substance has the same identity it becomes {blank}. ·          alkali metals: Group I in the periodic table. ·          alkaline earth metals: Group II in the periodic table. ·          alkane: An organic molecule which contains only single carbon-carbon bonds. ·          alkene: An organic molecule containing at least one C=C bond ·          alkyne: An organic molecule containing at least one C-C triple bond. ·          Viscosity: The resistance to flow by a fluid. ·          Pascal: Used to measure pressure. ·          Atom: Element composed of one type, the {blank}. · ...

Compare and contrast

Compare and contrast are multi-paragraph compositions that explain ways in which two (or, very occasionally, more) subjects are similar or different. In these article, compare means describing similarities between the subjects. When we are comparing Lithium and Calcium. Lithium Lithium (Li) is a silvery gray metal with an atomic number of three. While being the lightest metal under normal conditions, it is still the most dense. With an atomic number of three, lithium has three protons in the nucleus, but like many other alkalai metals it has only one valence electron. Interesting Lithium Facts: ·          It is the least reactive of the alkalai metals. ·          The nucleus of lithium is fairly unstable. ·          Because of this instability, lithium alone almost never appears in nature. · ...

Classification Of Matter

ATOMS The atom is the basic building block for all matter in the universe. Atoms are extremely small and are made up of a few even smaller particles. The basic particles that make up an atom are electrons, protons, and neutrons. Atoms fit together with other atoms to make up matter. It takes a lot of atoms to make up anything. There are so many atoms in a single human body we won't even try to write the number here. Suffice it to say that the number is trillions and trillions (and then some more). There are different kinds of atoms based on the number of electrons, protons, and neutrons each atom contains. Each different kind of atom makes up an element. There are 92 natural elements and up to 118 when you count in man-made elements. Atoms last a long time, in most cases forever. They can change and undergo chemical reactions, sharing electrons with other atoms. But the nucleus is very hard to split, meaning most atoms are around for a long time.  Structure of the Atom A...