Chemistry Notes – Grade 10
National Curriculum Pakistan - NCP
Chapter 5: Reaction Kinematics
Aligned with National Curriculum Pakistan (Federal Board, NBF, PTB)
- What are chemical reactions?
Chemical reactions are processes in which mass and energy are constantly changing. - Do chemical reactions occur at the same speed?
No, they occur at a range of speeds—from very fast to very slow. - Give an example of a slow reaction.
Fermentation is a slow reaction; it takes several weeks to produce enough products. - Is digestion a fast or slow reaction?
Digestion is considered a slow reaction. - Give an example of a fast reaction.
Acid-base neutralization is a fast reaction that takes only a few microseconds. - What are some examples of reactions that occur at a moderate speed?
Reactions involved in muscle contraction, nerve impulses, and capturing photographic images occur at a moderate speed. - Why is it important for industries to understand reaction conditions?
It helps them find the most cost-effective way to carry out reactions. - What is kinetics?
Kinetics, or chemical kinetics, is the study of the rate of chemical reactions, their mechanisms, and the factors that influence them. - What factors are studied under chemical kinetics?
Chemical kinetics studies reaction rates, mechanisms, and influencing factors. - What role does energy play in chemical reactions?
Energy is constantly changing during chemical reactions, along with mass. - What does the rate of a chemical reaction tell us?
It tells us how quickly reactants are used up or how quickly products are formed over time. It reflects the change in concentration of reactants or products in a given time. - What is the formula to calculate the rate of a chemical reaction?
Rate = Change in concentration of a substance / Time taken for change. - What are the units for the rate of a reaction?
The unit is typically mol dm⁻³s⁻¹ (moles per cubic decimeter per second). - What does the graph in Figure 5.1 represent?
It shows how the concentration of reactants decreases while the concentration of products increases over time during a chemical reaction. - What does it mean when the curve becomes less steep over time?
It means the reaction slows down as fewer reactant particles are available to collide and react. - What happens when the curve becomes flat?
The reaction has either stopped because all reactants are used up, or the system has reached equilibrium. - How can the average rate of reaction be calculated?
Average rate = Total change in concentration / Total time taken. - How can the rate of a reaction be expressed in terms of disappearance and appearance?
Rate = -d[A]/dt (for disappearance of A) or Rate = d[B]/dt (for appearance of B).
Tags
average rate of reaction
Chemical Kinetics
chemical reactions
factors affecting reaction rate
fast reactions
rate of reaction
reaction rate formula
reaction rates
slow reactions