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Some examples of chemistry in everyday life

Chemical properties are the characteristics of a substance that states whether the substance can Undergo certain chemical changes. Chemical change is a change that changes the identity of matter in a matter. In the chemical change formed a new substance. The occurrence of a chemical reaction can be known from the changes caused by the reaction. Some of these changes are the formation of sediment, the occurrence of color changes, the formation of gas, and the presence of temperature changes.

1.      Burning reaction

The combustion reaction is a type of redox reaction in which the fuel reacts with the oxidizing agent, thereby releasing energy as heat.This reaction is exothermic, which means that energy is released during the reaction. The endothermic reaction is one that absorbs heat. The typical combustion reaction has hydrocarbons as a fuel source, and oxygen gas as an oxidizer. Such a reaction product would be CO2 and H2O.

CxHyOz + O2 → CO2 + H2O (balanced)

Such a reaction would be a glucose burning in the following equation

C6H12O6 (s) + O2 (g) → CO2 (g) + H2O (g)

In real life for example explosion and burning.

2.       Precipitation Reactions

The reaction that occurs when the anions (negatively charged ions) of the solution and the cations (positively charged ions) combine to form the insoluble compound known as precipitation. The existing solution of the solid is called the precipitate, and the remaining liquid is called the supernatant. Example:

CaCO3 (aq) + H2SO4 (aq) → CaSO4 (s) + H2O (l) + CO2 (g)

3.       Acid-base Reactions or Neutralization Reactions

Neutralization reactions occur when acids and bases are mixed together. Acids are substances that produce H + ions in solution, while bases are substances that produce OH-ions in solution. A typical acid-base reaction will produce ionic compounds called salts and water. The typical acid-base reaction is a reaction between hydrochloric acid and sodium hydroxide. This reaction is shown by the equation:

HCl (aq) + NaOH (aq) → NaCl (aq) + H2O (l)

In this reaction, HCl is an acid, NaOH is a base, and NaCl is a salt.

An example in real life: Baking soda reacts with vinegar is a neutralizing reaction.

4.       Oxidation-Reduction or Redox Reaction

The redox reaction occurs when the oxidation number of the atoms involved in the reaction changes. Oxidation is the process by which the oxidation number of atoms increases, and reduction is the process by which the atomic oxidation number decreases. An oxidized atom is called a reducing agent, and a reducing atom is called an oxidizer. An example of a redox reaction is the reaction between hydrogen gas and fluorine gas:

H2 (g) + F2 (g) → 2HF (g)

In this reaction, the hydrogen is oxidized from the oxidation number from 0 to 1, and thus a reducing agent. Fluor decreases from 0 to -1, and thus is called an oxidizing agent.

5.       Formal Reaction

The forming reaction occurs when one or more compounds react to form a complex compound. An example of such a reaction is a silver reaction with oxygen gas forming a silver oxide:

2ag (s) + O2 (g) → 2AgO (s)

Examples in real life are Hydrogen gas burned in air (reacts with oxygen) to form water:2H2 (g) + O2 (g) → 2H2O (l)

6.      Decomposition Reactions

The decomposition reaction is the opposite of the forming reaction. During the decomposition reaction, more complex compounds break down into some simpler compounds. A classic example of this type of reaction of decomposition of hydrogen peroxide into oxygen and hydrogen gas:

2O2 (l) → H2 (g) + O2 (g)

7.       Chemical Reactions Produce Sediment

Around us there are many chemical reactions that can produce sediment. Reactions that include examples of chemical reactions that produce precipitates include:

Occurrence of carbonate compounds at the bottom of the pan when boiling water.

When lime water is blown, there will be a reaction between lime water and carbon dioxide from the breath. The occurrence of the reaction can be observed the formation of white calcium carbonate (CaCO3) that settles on the bottom of the glass if left for a while.Precipitation by chemical reactions has long been used for water purification processes. The muddy well water mixed with mud can be clarified with the addition of alum. Tawas will tie the particles of mud particles to clot and eventually settle.

8.       Chemical Reactions Produce Color Changes

Apples that are cut and left for a while, over time will be Turn brown. This color change indicates that the chemicals in apples have reacted with oxygen in the air. The reaction between the starch starch solution with iodine tintur can be known from the color change that occurs. Color clear starch solution, brown iodine. If both are mixed will form a blue color. If added vitamin C then iodine will react with vitamin C to form other chemicals that are colorless. So the occurrence of chemical reactions can be known from the color changes that occur. Household tools made of metal, these objects will gradually change color. The tool of iron will rust so that it becomes black, copper tools will change color to greenish, the tool from silver will change color to black. The color change indicates that there has been a chemical reaction to the devices. The color of the clothes we wear will fade as it reacts with the chemicals contained in the detergent.

9.       Chemical Reactions Produce Gas

In everyday life, many of us encounter marked chemical reactions,With the formation of gas. When the carbide is mixed with water, it will Produce carbide gas. This gas is generally used for purposes Metal welding. In addition, carbide gas can also Used to speed up the ripening of the fruit. When making a cake, into the dough is added baking soda. As the dough is heated, baking soda will break down producing carbon dioxide gas. Gas is what causes the cake to expand.

10.   Chemical Reactions Produce Temperature Changes

A firecracker explosion is the result of a chemical reaction. All reactions alwaysInvolving energy, some reactions absorb energy and some are releasing energy. The energy that accompanies the chemical reaction is heat, light, sound, or electrical energy. A chemical reaction that produces energy is called an exothermic reaction. If the energy is hot, it can tell by measuring its temperature rise. The combustion reaction is an example of an exothermic reaction.

When reacting with water, we can feel the increase The temperature on the glass wall where the reaction is performed. Large temperature rise can Measured with a thermometer. A chemical reaction that requires energy Called endothermic reactions. For example, a reaction to the photosynthesis process.