Term 1 Chemical Reaction Flashcards
Define a chemical reaction
the processes by which chemicals interact to form new chemicals with different compositions. Reactants are transformed into products.
Define activation energy
The minimum energy needed to start a chemical reaction by breaking the bonds of reactant molecules.
Explain how a chemical reaction occurs in terms of particles, collisions and energy
Chemical reactions occur when particles collide with sufficient energy to overcome activation barriers, leading to the formation of new chemical bonds and products
How does concentration affect rate of reaction
Increasing the concentration of reactants increases the frequency of collisions between particles, leading to more effective collisions and a higher reaction rate.
How does surface area affect rate of reaction
A larger surface area exposes more reactant particles to collisions, increasing the frequency of collisions and thus the reaction rate.
How does temperature affect rate of reaction
Higher temperatures increase the kinetic energy of particles, leading to more frequent and energetic collisions. This enhances the likelihood of successful collisions and accelerates the reaction rate.
How does a catalyst affect rate of reaction
Catalysts provide an alternative reaction pathway with a lower activation energy. This lowers the energy barrier for the reaction, allowing more particles to overcome it and participate in the reaction. Consequently, catalysts increase the reaction rate without being consumed themselves.
Describe the synthesis chemical reaction
A synthesis reaction, also known as a combination reaction, occurs when two or more reactants combine to form a single product.
General Form: A + B → AB
Describe the decomposition chemical reaction
A decomposition reaction occurs when a single compound breaks down into two or more simpler substances.
General Form: AB → A + B
Describe the double displacement chemical reaction
A double displacement reaction, also known as a metathesis reaction, occurs when the positive and negative ions of two ionic compounds exchange places to form two new compounds.
General Form: AB + CD → AD + CB
Use solubility rules to determine if a precipitate will form when two solutions are mixed
Identify ions present.
Predict possible products.
Focus on insoluble compounds.
Consider exceptions.
Factor in ion concentrations.
Explain an exothermic reaction
An exothermic reaction is a chemical reaction that releases energy in the form of heat to its surroundings. In simpler terms, it’s a reaction where heat is given off rather than absorbed. This release of energy usually results in an increase in temperature in the surroundings.
The energy profile diagram shows that the energy of the reactants is higher than that of the products, indicating a net release of energy.
Explain an endothermic reaction
An endothermic reaction is a type of chemical reaction that absorbs energy from its surroundings in the form of heat. In contrast to exothermic reactions which release heat, endothermic reactions require an input of energy to proceed. This energy is typically absorbed from the surroundings, causing a decrease in temperature in the vicinity of the reaction.
The energy profile diagram shows that the energy of the reactants is lower than that of the products, indicating a net absorption of energy.
