Kinetics
If 50.0 grams of calcium carbonate (CaCO3) react with excess hydrochloric acid (HCl), what mass of carbon dioxide (CO2) will be produced according to the reaction CaCO3(s) + 2HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)?
11.0 grams
22.0 grams
44.0 grams
33.0 grams
The decomposition of a pestecide compound applied to crops results in a first-order reaction with 56 days as its half-life. What is the rate constant?
56 day^-1
0.012 day^-1
81 day^-1
0.018 day^-1
Which of the following factors would most significantly affect the rate-determining step of a complex reaction mechanism?
Concentration of products in the final step.
Activation energy of the fastest elementary step.
Overall enthalpy change of the reaction.
Activation energy of the slowest elementary step.
Why does an increase in temperature usually increase reaction rates?
Increase molecules' kinetic energy causing more collisions with enough energy to surpass activation barrier
Speeds up diffusion mixing reagents quicker but without necessarily increasing collision energy
Directly lowers activation energy allowing easier formation of products
Increases solvent viscosity reducing effective collision frequency between particles
Given four substances with nearly identical molecular weights, which would have the highest boiling point based on its dominant intermolecular forces?
Nitrogen gas (N2), due to London dispersion forces.
Methane (CH4), due to London dispersion forces.
Carbon monoxide (CO), due to dipole-dipole interactions.
Hydrogen fluoride (HF), due to hydrogen bonding.
How do you calculate moles from molarity and volume?
Multiply molarity by volume
Divide density by molarity
Multiply volume by density
Add mass to volume
What is typically observed when a catalyst is added to a reaction mixture at constant temperature?
The equilibrium position shifts towards products, increasing their concentration over time.
The reaction rate increases due to a lower activation energy pathway being provided.
The reaction enthalpy changes, leading to higher product yields without affecting rate.
A decrease in reaction rates occurs as catalysts introduce alternative endothermic pathways.

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What happens to the half-life of a second-order reaction when the initial concentration of reactants is doubled?
The half-life doubles.
The half-life increases by four times.
The half-life remains unchanged.
The half-life decreases by half.
What does the reaction order n describe in a rate law?
The duration of the chemical reaction
The level of complexity of the chemical reaction
The velocity at which molecules collide
The effect of molecule concentration on the reaction rate
What is plotted for a first order reaction? What is the lines slope?
ln[A] vs time, -k
ln[A] vs time, k
[A] vs time, -k
1/[A] vs time, k