Introduction to Chemical Reactions Video Lecture - Class 10

Ans. Chemical reactions are processes in which substances, known as reactants, undergo a transformation to form new substances, called products. During a chemical reaction, bonds between atoms are broken and new bonds are formed, resulting in a rearrangement of atoms.

Ans. There are several types of chemical reactions, including: - Combination or synthesis reactions: Two or more substances combine to form a single product. - Decomposition reactions: A single compound breaks down into two or more simpler substances. - Displacement or replacement reactions: An element in a compound is replaced by another element. - Double displacement or metathesis reactions: The positive and negative ions of two compounds exchange places. - Redox reactions: Involves the transfer of electrons between reactants. - Acid-base reactions: Involves the transfer of a proton (H+) from an acid to a base.

Ans. Chemical reactions can be represented using chemical equations. A chemical equation consists of reactants on the left side of an arrow and products on the right side. The arrow indicates the direction of the reaction. Coefficients are used to balance the number of atoms on each side of the equation.

Ans. A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. It works by providing an alternative pathway for the reaction to occur, lowering the activation energy required. Catalysts remain unchanged at the end of the reaction and can be reused.

Ans. Several factors can affect the rate of a chemical reaction, including: - Concentration of reactants: Increasing the concentration of reactants generally increases the rate of reaction. - Temperature: Higher temperatures usually lead to faster reactions as it provides more energy for particles to collide. - Surface area: A larger surface area of reactants allows for more collisions to occur, increasing the rate of reaction. - Presence of a catalyst: Catalysts can speed up reactions by providing an alternative pathway with lower activation energy. - Pressure (for gaseous reactions): Increasing pressure can increase the rate of reaction by bringing particles closer together and promoting more collisions.