Atoms
An atom is the smallest indivisible particle of an element. Atoms cannot be seen by the naked eye because they are so tiny. The smallest dot on a paper may have up to two million atoms. Two or more atoms combine to form molecules. A molecule is the smallest, independent particle of a pure substance. Atomicity is a term used to describe the number of atoms in a molecule. A water molecule with two hydrogen atoms and one oxygen atom would have atomicity of three. A molecule can be homoatomic, i.e., made up of similar atoms, or heteroatomic, i.e., made up of different atoms. Ozone (O3), Oxygen (O2), and hydrogen (H2) molecules are homoatomic, while water (H2O) is a heteroatomic molecule.

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Monocots and Dicots
Flowering plants are classified into monocots and dicots. The names of these classifications are based on how many cotyledons a seedling has inside its seed. A monocot, or a monocotyledon, has a single cotyledon, whereas a dicot, or a dicotyledon, has two cotyledons. Dicot plants have branched veins in their leaves. Usually, side veins branch out from the center vein on either side of the leaf, similar to a feather. Veins in monocots’ leaves run parallel to one another. Flowers of monocots have floral components in groups of three or multiples of three. Floral components of dicots’ flowers are multiples of four or five.

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pH Value
The pH scale can determine an aqueous solution’s acidity or basicity. Since pH is essentially a measurement of the concentration of hydrogen ions present in a substance, the letters pH stand for the potential of hydrogen. The pH scale range from 0-14 by convention because the pH value of 1 molar hydrogen ions is not more than 0, and the pH value of 1 molar hydroxide ions is not more than 14. A solution with a pH below seven is considered acidic, and one over seven is basic or alkaline. A solution with a pH of 7 is a neutral solution.

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Solution
Any mixture of one or more solutes dissolved in a solvent is a solution. A solute is anything being dissolved, and the solvent is the substance in which solute is added and dissolved. For example, if we dissolve sugar or salt in water, it becomes a solution. In this case, sugar or salt are solutes because these are the substances being dissolved, and water is a solvent because it dissolves solutes, i.e., sugar or salt. A solute in the solution is usually contained in smaller amounts, while the solvent is in larger amounts. Many solutions are based on the physical states of solute and solvent. A solution can be made of gas only if both solute and solvent are in a gaseous state or liquid only if both solute and solvent are liquid. Similarly, it can be made of gas and liquid if the solute is gas and solvent is liquid or even solid and liquid if the solute is solid and solvent a liquid.

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Reactions
Catalysts are substances that speed up any chemical reaction. The enzyme is a protein that acts as a biological catalyst in living things, controlling the pace at which chemical reactions occur without changing themselves. Enzymes are classified into six types based on the type of reaction they catalyze. These six types include oxidoreductases, hydrolases, transferases, lyases, isomerases, and ligases. Oxidoreductase enzymes speed up the oxidation reactions, which involve the transfer of electrons from one molecule to another. Transferases enzymes aid in the transfer of the functional groups among molecules. Similarly, hydrolase enzymes catalyze the reactions which involve the breakage of water molecules (i.e., hydrolysis reactions).

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Titration
Titration is the determination of unknown strength using a solution of known strength or concentration. There are multiple titrations, including acid-base titration, redox titration, precipitation titration, and complexometric titration. An acid-base titration is used to find out the strength of acid using the known strength of a base. It is also known as acidimetry. Similarly, the unknown strength of the acid can also be used to determine the strength of a base, this process is known as alkalimetry. In redox titrations, a redox or oxidation-reduction reaction is involved. In precipitation titration, the soluble precipitate is formed due to the reaction.

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