Unit 10: Rates of Reaction Mini-Unit Review

A set of vocabulary flashcards based on the Unit 10 lecture notes covering the mechanics of reaction rates, collision theory, and experimental rate calculations.

Rate of Reaction

The change in concentration of a reactant or product over a period of time, calculated using the change in concentration divided by the change in time.

Collision Theory

The theory stating that for a chemical reaction to occur, particles must collide with both enough energy and correct orientation.

Concentration

A factor affecting the rate of reaction where an increase provides more particles in the same volume, leading to more frequent collisions per unit time.

Temperature

A factor affecting the rate of reaction where an increase results in higher kinetic energy of particles, making collisions more frequent and energetic (more particles reach the activation energy).

Surface Area / Particle Size

The amount of exposed area of a solid reactant; decreasing particle size increases this factor, providing more space for collisions to occur and thus increasing the reaction rate.

Catalyst

A substance that increases the rate of reaction by providing an alternative pathway with a lower activation energy ($E_a$).

Average Rate of Reaction

The rate of a chemical reaction calculated over a specific interval of time using the formula $\frac{\Delta [\text{Concentration}]}{\Delta t}$.

Instantaneous Rate of Reaction

The rate of reaction at a specific moment in time, determined graphically by calculating the slope of the tangent line to the concentration-time curve at that time.

$N_2O_5$ Decomposition

A reaction mentioned where concentration decreases from $0.60\,M$ to $0.02\,M$ over a period of $100\,s$.

Hydrogen Peroxide Decomposition

A chemical process following the equation $2H_2O_2(aq) \rightarrow 2H_2O(l) + O_2(g)$, used to calculate rates based on volume or concentration changes over time.

Calcium Carbonate and HCl Reaction

A reaction between marble chips ($CaCO_3$) and hydrochloric acid ($HCl$) that produces carbon dioxide gas ($CO_2$) and can be monitored by measuring the mass loss of the flask and contents.

Limiting Reactant

The reactant that is completely consumed in a reaction and determines when the reaction stops, such as calcium carbonate in the experiment with $40\,cm^3$ of $1\,M\,HCl$.