Railway Science (Chemistry-Chemical Reaction) (Part-II)

Decomposition reaction - It is defined as the reaction in which a single compound splits into two or more simple substances under suitable conditions. It has three types - Thermal decomposition, Electrolytic decomposition, and Photo decomposition. It is given by AB → A + B. Example - H₂CO3 → H₂O + CO₂ , (H₂CO₃) - Carbonic acid.

The reaction is a double replacement reaction between barium chloride and copper(II) sulfate resulting in the formation of aqueous copper(II) chloride and the water insoluble barium sulfate which precipitates out of the solution as a solid.

CaCO₃ (limestone) → CaO (Calcium Carbonate) + CO₂ (Carbon dioxide). CaCO₃ is a white insoluble powder - like substance which occurs naturally in minerals, chalk, marble, limestone, calcite, shells, pearl, etc.
It is used as an ingredient in cement, calcium supplements, medicinal industries and in manufacturing of paints and plastics.

Fe (s) + CuSO₄(aq) → FeSO₄(aq) + Cu(s) is a displacement reaction. Displacement reaction is a chemical reaction in which a more reactive element displaces a less reactive element from its compound. CaCO₃ (s) → CaO(s) + CO₂ (g) and ZnCO₃(s) ZnO (s) + CO₂ → (g) are decomposition reactions. 2H₂ (g) + O₂ (g) → 2H₂O (l) is an addition reaction.

In this reaction, CuS𝑂₄ + Mg → MgS𝑂₄ + Cu. Mg is acting as a reducing agent because it has reduced the CuS𝑂₄ to Cu. Reducing 4 Agent is one of the reactants of an oxidation-reduction reaction which reduces the other reactant by giving out electrons to the reactant.
Oxidizing agent is a substance that oxidizes other substances involved in the reaction by gaining or accepting electrons from them. Catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process.

The chemical reaction is Na₂S + 2HCl → 2NaCl + H₂S↑. Hydrogen sulfide is a flammable, colorless gas with a characteristic odor of rotten eggs. It is commonly known as hydrosulfuric acid, sewer gas, and stink damp. It can also cause apnea, coma, convulsions, dizziness, headache, weakness, irritability, insomnia,etc.

Balanced equation is an equation for a chemical reaction where the number of atoms of each type in the reaction is the same on both reactants and product sides. Hydrogen bromide (HBr) is highly corrosive and irritating to inhalation. It is used in making chemicals and pharmaceuticals, as a catalyst, and for dissolving oils.

Baking soda is also known as Sodium bicarbonate. It is basic in nature. Reduces the acidity in the stomach. Used in the process of washing as a water softener.

Keeping food in airtight containers helps in slowing down the oxidation. The potato chips manufacturer uses nitrogen gas to fill the chips bags to prevent the chips from getting oxidized in presence of oxygen from the atmosphere.

Chemical equations are written in a standard format. The reactants are listed on the left side of the equation, while the products are listed on the right. The direction of the reaction is shown by an arrow pointing from the reactants to the products.