#9thclasschemistry #newbook2025 #equilibria Reversible and irreversible changes
TEXT BOOK PAGE NUMBER: 83 & 84 (first paragraph) Note: In this video the wordings are same as in the text book. Write Headings on your book. Notes are in description.  🔹 6.1 Reversible and Irreversible Changes  🔸 Irreversible Reaction In a chemical reaction, the reactants react to give the products. The reaction will continue until all the reactants or one of the reactants is converted into product. For example, the following reaction takes place immediately in an aqueous solution to give the products. NaCl (aq) + AgNO₃ (aq) → AgCl (s) + NaNO₃ (aq) The reaction goes to completion and if stoichiometric amounts of the reactants are used then no reactant species are present at the end of the reaction. ✅ Such a reaction is called an irreversible reaction. It moves in the forward direction only.  🔸 Reversible Reaction In the majority of chemical reactions, however, the reaction does not go to completion. The products of the reaction act among themselves to give back the reactants under the same conditions. Such a reaction moves in both the forward and backward directions at the same conditions. The reactants react to give the products and the products inturn react to give back the reactants. ✅ The reaction is called a reversible reaction and it is denoted by a symbol ⇌ which has two half arrowheads one pointing in each direction. For example, N₂ (g) + 3H₂ (g) ⇌ 2NH₃ (g) 400°C, 200 atm (Fe)  🔸 Explanation of Ammonia Synthesis as a Reversible Reaction In this reaction, one mole of nitrogen gas reacts with three moles of hydrogen gas under the given reaction conditions in a closed container to give two moles of ammonia gas. After its formation, the ammonia gas decomposes to give the reactants back. The reaction never goes to completion. At any time, all the three species are simultaneously present in the reaction mixture. #9th #chemistry #newbook2025 #Equilibria #reversiblereaction #irreversiblereaction #Dynamicequilibrium #exerciseschapter6chemistry9th #timetoattaindynamicequilibrium #changingthephysicalconditionsofachemicalreaction #Effectofchangeinreactantofproductconcentration #Effectofchangingthetemperatureonthestateofequilibrium #Effectofchangeofpressureonthereactionatequilibrium #effectofpresenceofcatalystonthereversiblereaction #ExerciseMcqschapter6 #exerciseshortanswerschapter6 #exerciseconstructedresponsequestionschapter6 #exercisedescriptivequestionschapter6 #exerciseinvestigativequestionschapter6 #Class9Chemistry2025 #PunjabBoardChemistry9 #ChemistryChapter6Explained #9thChemistryPlaylist #LearnEquilibria #EquilibriumMadeEasy
