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Chemical principles are quite diverse and fundamentally important, including brain functioning, computer operations, weather patterns, chemical industries, manufacturing fertilizers, acids, alkalis, salts, drugs, soaps, and so on. Chemistry is also a major determinant in meeting human needs for food, healthcare products, and other materials aimed at improving the quality of life.
Nature of matter
Everything around us, including the pen, book, pencil, air, and all living beings, is made up of matter. Only physical means are used to move matter from one phase to another. If energy is added, the temperature rises; if energy is removed, the temperature falls; and something is frozen. Matter exists in three physical states, namely solids, liquids, and gases.Solids are particles that are held together very tightly and do not have enough freedom to move. The solids have a distinct volume and shape.Ceramic bowls, for example, are made of soft clay and are heated before being slowly cooled. As the water is removed, the clay hardens and the chemical bonds within the clay change.Liquids are particles that are close together but have the ability to move around. They have a fixed volume but no fixed shape, so they take on the shape of the container. Oceans, lakes, and rivers are examples of liquids.These three states of matter are easily interconvertible by varying the pressure and temperature conditions.
Laws of chemical combination
The law of conservation of mass states that “matter cannot be created or destroyed.” This simply means that the number of reactants used in the reaction equals the number of products formed.
The law of definite proportions states that any compound always contains its constituents in the same fixed ratio by mass, regardless of its source or method of preparation.
The law of multiple proportions states that when two elements combine to form one or more compounds, the masses of one element that combine with the other element have a small whole number ratio.
Stoichiometry and Stoichiometric Calculations
This concept aids us in calculating the mass or quantity of reactants and products in a given chemical reaction. We must first have a balanced chemical equation before we can predict the mass of reactants and products. As an example,
The following is the chemical reaction:
Because this chemical equation is balanced, we can predict that one mole of oxygen will combine with two moles of hydrogen to form two moles of water, and thus we can calculate the masses of the respective elements.
We also learn about the “limiting reagent” in this concept. It is the substance that is present in smaller amounts in reactants. To put it another way, a limiting reagent is a substance that will be completely finished or react in the given chemical reaction.
Some important formulas in the basic chemistry
The mole fraction is the ratio of the moles of any substance in the solution to the total moles of the solution. It is shown mathematically as :
where nA denotes the mole of component A and nB denotes the mole of component B.
The concentration of any substance present in the solution is referred to as its molarity. In other words, it is the number of moles of solute per liter of solution. It is shown mathematically as :
Molality refers to the number of moles of solute dissolved in a given amount of solvent. It is shown mathematically as :
Normality is defined as the number of solute equivalents dissolved in one liter of solution. It is shown mathematically as :
Boyle’s Law
The gas volume is affected by temperature and pressure. At constant temperature, the volume (V) of a definite quantity of gas is inversely proportional to its pressure (P), according to Boyle’s law (T).
P1V1 = P2V2
Charles’s Law
At constant pressure, the volume (V) of a definite quantity of gas is directly proportional to its absolute temperature (T) according to Charles’s Law (P).
V1/V2 = T1/T2
Numerical example of basic chemistry
Q:Determine the molecular weight of Ammonium Sulfate (NH4)2SO4.
the relative atomic masses be:
N = 14, H = 1, S = 32, O =16
Therefore, the molecular mass of the given compound is,
= 2 (14 × 1 + 1 × 4)+ 32 + 16 × 4
= 2(14+4)+32+64
= 2 × 18+32+64
= 36+32+64
= 132 amu
Conclusion
Scientists, including chemists, study the world in a systematic manner. Learn how to collect data and design experiments using the scientific method. Elements being the fundamental building blocks of matter. Find out what an element is and how to get facts about it. The periodic table is a method of organizing elements based on their similar properties. Discover what that table is, how it was created, and how you can use it to make your chemistry studies much easier.
