AP Chemistry FRQ Room

Coulomb's Law and Electron Removal Energy

This question requires the application of Coulomb's Law to quantify the electrostatic force between

Coulomb's Law and Ionization Energy

Consider an atom in which an electron is located at a distance of $$1.0\times10^{-10}$$ m from the n

Determination of Percent Composition in Calcium Nitrate

A sample of calcium nitrate, $$Ca(NO_3)_2$$, is analyzed to determine its percent composition. A res

Effects of Shielding on Atomic Radius

In an atomic physics study, the researcher examines how inner electrons affect the size of the atom

Electrode Potential Measurement in Galvanic Cell Experiment Error

A student assembles a galvanic cell using zinc and copper electrodes to measure the cell potential u

Electron Configuration and Periodic Trends

Consider the electron configurations of elements across a period and the resulting periodic trends.

Electron Configuration Diagram Analysis

Given the electron configuration diagram for elements in the third period, identify the element with

Empirical and Molecular Formula Analysis

A compound was found to have the following percent composition: 40.0% C, 6.7% H, and 53.3% O. The mo

Empirical and Molecular Formula Determination

A compound is analyzed and found to have the following percent composition: 40% carbon, 6.7% hydroge

Evaluating Electronegativity Differences by Measuring Bond Energies

Electronegativity differences between atoms affect the bond energy in diatomic molecules. Design an

Ideal Gas Law and Mole Determination

An unknown gas is studied at STP. The following experimental data were recorded: Volume = $$22.4$$ L

Ideal Gas Law Application under Non-STP Conditions

A gas is contained in a 2.00 L vessel at an initial pressure of 1.50 atm and temperature of 350 K. C

Ionic Charges and Compound Formation

A chemist is studying the formation of ionic compounds by predicting ionic charges based on periodic

Isotopic Abundance and Atomic Mass Determination

Element X has two naturally occurring isotopes with the following data: Isotope A: 35 amu (75% abund

Le Chatelier’s Principle in Industrial Equilibrium

Consider an industrial equilibrium reaction involving gaseous reactants and products. The graph prov

Mass Spectrometry Isotope Abundance Analysis Error

A researcher uses mass spectrometry to analyze the isotopic composition of selenium. The procedure i

Molarity and Dilution Calculations

Solve problems involving molarity calculations and the dilution of solutions.

Molarity and Dilution Calculations in Solution Preparation

A researcher needs to prepare 250 mL of a 0.500 M sodium chloride (NaCl) solution from a stock solut

Molarity in Reaction Kinetics

In a kinetics lab, the concentration of an acid solution is monitored during a titration experiment.

Mole Conversions: From Mass to Particles

A researcher is investigating fundamental mole conversions through experiments with carbon. Using th

Periodic Table and Isotope Analysis

This question examines your understanding of periodic table notations and isotope abundance calculat

Periodic Trends: Atomic Radii Analysis

A graph plotting atomic radii against atomic number across a period shows a steady decrease in radii

Photoelectron Spectroscopy Analysis

This question analyzes a photoelectron spectrum (PES) to deduce information about the electronic str

Selenium Mass Spectrometry Analysis

Analyze a mass spectrometry data set for selenium to determine key isotopic information and assess m

Analyzing Hybridization in a Coordination Complex: [Co(NH₃)₆]³⁺

This question involves the analysis of a coordination complex to determine oxidation state, hybridiz

Analyzing Lattice Energy in Ionic Solids

A journal article posits that lattice energy in ionic solids is solely determined by the product of

Bond Order and Bond Length Analysis in Diatomic Molecules

Explore the relationship between bond order and bond length in diatomic molecules using provided exp

Conductivity and Phase Change in Ionic Substances

Electrical conductivity varies with the phase of the substance. Using the conductivity table provide

Covalent Bonding and Internuclear Distance Analysis

Analyze how the internuclear distance affects the potential energy in covalent bonds using a potenti

Effect of Ion Size and Charge Density on Bond Strength

Use Coulomb's law to analyze how differences in ion size and charge density affect the strength of i

Evaluating PF5: Expanded Octet and Molecular Geometry

Phosphorus pentafluoride (PF5) is a classic example of a molecule that involves an expanded octet. E

FRQ 4: Molecular Geometry – VSEPR Analysis

A table is provided listing various molecules along with their central atom electron pair counts and

FRQ3: Analyzing Covalent Bonding, Bond Lengths, and Molecular Shapes

A research group investigates covalent bonding behaviors by studying potential energy variations as

FRQ13: Quantitative Analysis of Coulomb's Law in Ionic Crystals

A theoretical study is conducted where students calculate ionic bond energies using Coulomb’s law. G

FRQ19: Impact of Ionic Radii on Lattice Structures

The lattice structure of ionic compounds depends significantly on the sizes of the constituent ions.

Interatomic Potential Energy and Internuclear Distance

A graph displays the potential energy (in kJ/mol) as a function of internuclear distance (in Å) for

Interpreting Metallic Bonding Representations

Metallic bonding is characterized by a lattice of positive ions immersed in a 'sea of electrons'. An

Ionic Lattice Energy Comparison

Consider several ionic compounds such as NaCl, MgO, and Al2O3. Each compound is composed of ions wit

Lewis Dot Structures and Covalent Bonding

Water (H2O) serves as a classic example of a covalent molecule. Using your knowledge of Lewis dot st

Metallic Bonding and Electrical Properties

A researcher publishes a claim that all metals, due to their 'sea of electrons,' exhibit maximum ele

Molecular Geometry Determination and VSEPR Theory

A chemist is examining a molecule with the general formula $$AX_4E_1$$, where A is the central atom,

Phase Transitions and Conductivity of Ionic Compounds

A physical chemist is examining how the electrical conductivity of an ionic compound changes as it t

Resonance Stabilization in Benzene

Benzene is known for its exceptional stability, which is attributed to resonance and aromaticity. Ex

Structure and Properties of Metallic Alloys

Examine the differences between interstitial and substitutional alloys with respect to their structu

Bond Polarity in NH3 vs. PH3

Compare and contrast the bond polarity and overall molecular polarity in ammonia (NH3) and phosphine

Chromatography Data Analysis for Ink Separation

Analyze the chromatographic separation of ink components to determine the polarity of the pigments.

Column Chromatography: Effect of Solvent Polarity

This question focuses on column chromatography and how the polarity of the mobile phase influences t

Combined Gas Law Application

A sample of gas initially has a pressure $$P_{1}= 2\ \text{atm}$$, a volume $$V_{1}= 10\ \text{L}$$,

Dalton’s Law and Partial Pressure Calculation

A container holds a gas mixture with a total pressure of 2.50 atm. The mixture consists of 0.20 mol

Dalton's Law in Gas Mixtures

In an experiment, a container holds a mixture of gases at a total pressure of 3.0 atm. The moles of

Density and Molar Mass Calculation from Gas Density

A gas is measured to have a density of $$D = 1.25\ \text{g/L}$$ at 1.00 atm and 300 K. Answer the fo

Designing a Column Chromatography Experiment

Column chromatography utilizes polarity differences to separate mixtures. Develop an experimental de

Determining Gas Molar Mass from Density

The density of a gas can be used to determine its molar mass by the equation $$MM = \frac{D*R*T}{P}$

Effusion Rate Analysis Using Graham’s Law

Effusion is the process by which gas molecules escape through a small opening. Graham's Law, express

Effusion Rate Comparison and Molar Mass Ratio

Using kinetic molecular theory and Graham’s Law, analyze the relationship between effusion rates and

Electronegativity, Bond Types, and Polarity

The difference in electronegativity between two atoms determines the bond type (nonpolar covalent, p

Hydrogen Bonding in Water vs. Ammonia

A researcher investigates the role of hydrogen bonding in determining the physical properties of wat

Intermolecular Forces and Phase Change Observations

In a laboratory experiment, a liquid known to engage in moderate hydrogen bonding is heated until it

Intermolecular Forces and Phase Transitions Analysis

A claim has been made that substances with stronger intermolecular forces (IMFs) have higher boiling

Intermolecular Forces Comparison

A student compares the boiling points of water (H2O), ammonia (NH3), and methane (CH4) to understand

Investigation of Gas Effusion Rates in Micro-Perforated Containers

A student designs an experiment to study the effusion of a gas using a container with micro-perforat

Molecular Geometry and Polarity Exceptions

This question asks you to analyze how molecular geometry and the presence of lone pairs affect molec

Molecular Geometry and Polarity in NF3 versus NH3

Compare the molecular structures of NF3 and NH3 to determine how geometry and electronegativity infl

Molecular Polarity and Geometry Analysis

An environmental chemist is studying potential atmospheric pollutants. Two molecules of interest are

Paper Chromatography and Polarity

Analyze the separation of an ink mixture using paper chromatography and relate the retention factor

Paper Chromatography and Polarity Separation

Paper chromatography separates mixtures based on differences in solute-solvent interactions and pola

Paper Chromatography Separation of Pigments

In paper chromatography, the separation of mixture components depends on solute–solvent polarity int

Quantitative Analysis Using Beer’s Law for Concentration Determination

Utilize the provided absorbance data to explore the relationship between concentration and absorbanc

Solvent Effects on Reaction Rates and Equilibrium

Examine the effect of solvent polarity on solubility and reaction kinetics.

Analysis of Solubility Product in a Precipitation Reaction

A student determines the solubility product (Ksp) of a sparingly soluble salt by preparing a saturat

Balancing Chemical Equations and Percent Error Calculation

This FRQ covers balancing chemical equations and percent error analysis. You are provided with a rea

Balancing Complex Chemical Equations and Reaction Mechanism Analysis

Ammonium dichromate decomposes according to the reaction: $$ (NH_4)_2Cr_2O_7 \rightarrow Cr_2O_3 + N

Chemical Equilibrium: Le Chatelier’s Principle

For the equilibrium reaction $$N_2 (g) + 3*H_2 (g) \rightleftharpoons 2*NH_3 (g)$$, analyze the syst

Classification and Balancing of Chemical Reactions

A laboratory exercise provides a series of unbalanced chemical reactions involving synthesis, decomp

Combustion Reaction Analysis and Empirical Formula Determination

A hydrocarbon underwent complete combustion in a controlled experiment. The following table with com

Combustion Reaction Mechanisms and Energy Calculations

Butane ($$C_4H_{10}$$) combusts according to the reaction: $$C_4H_{10} + \frac{13}{2} O_2 \rightarro

Decomposition Reaction Analysis

A decomposition reaction following the form AB → A + B was studied at various temperatures. The foll

Experimental Design: Reaction Rate and Stoichiometry

Design an experiment to investigate the reaction rate of a synthesis reaction where multiple variabl

FRQ 12: Interpreting a Graph of Reaction Kinetics

A graph is provided showing the natural logarithm of the reactant concentration (ln[A]) versus time

Gravimetric Analysis of Alkali Hydroxide

A 4.33 g sample of an unknown alkali hydroxide is completely dissolved in water. An excess of copper

Gravimetric Analysis of an Alkali Hydroxide

In a gravimetric analysis experiment, a 4.33 g sample of an unknown alkali hydroxide (either LiOH, N

Gravimetric Analysis: Identification of a Metal Ion via Precipitation

An unknown solution containing a trivalent metal ion \(M^{3+}\) is treated with a base to precipitat

Gravimetric Precipitation of an Unknown Carbonate

A student performs a gravimetric analysis to determine the carbonate content in an unknown mineral s

Investigation of Reaction Mechanisms

A researcher is studying the mechanism of a reaction that produces an intermediate species during th

Investigation of Synthesis Reaction Yield

An experiment was conducted to study a synthesis reaction represented by A + B → AB under varying te

Oxidation States in Complex Molecules

Determine the oxidation states for elements in the following compounds: $$KMnO_4$$, $$HNO_3$$, and $

Precipitation Reaction and Solubility Rules

In an experiment involving the mixing of various aqueous salt solutions, a researcher observes the f

Precipitation Reaction: Gravimetric Analysis of an Ion

A lab experiment investigates the precipitation reaction of ion X+ with reagent Y to form an insolub

Precipitation Reaction: Mechanism Identification

In an experiment, two aqueous solutions were mixed and a solid precipitate was observed to form. Add

Redox Titration Analysis Using KMnO4

In a redox titration, potassium permanganate ($$KMnO_{4}$$) is used to determine the concentration o

Redox Titration Data for Determining Concentration of an Unknown

A redox titration is performed using a 0.05 M KMnO₄ solution to determine the concentration of an un

Redox Titration for Concentration Analysis

A redox titration is performed to determine the concentration of an unknown $$Fe^{2+}$$ solution usi

Solubility and Precipitation Reactions Analysis

Consider the precipitation reaction: $$A (aq) + B (aq) \rightarrow C (aq) + D (s)$$, and the solubil

Arrhenius Equation and Temperature Dependence

A reaction’s rate constant k was determined at various temperatures. The following data was obtained

Arrhenius Plot Interpretation

A series of experiments were conducted to determine the temperature dependence of a reaction rate. T

Comparative Analysis of Reaction Orders Based on Experimental Data

Three different experiments are provided, each believed to represent a reaction with zero-, first-,

Comparative Graph Analysis for Integrated Rate Laws

An experiment was conducted to determine the order of a reaction by plotting different transformatio

Comparing Experimental and Theoretical Rate Laws

For a reaction, experimental kinetics yield a rate law of $$\text{Rate} = k [A]^2 [B]$$, while theor

Derivation of Overall Rate Law for a Pre-Equilibrium Mechanism

Consider the following mechanism: Step I (fast equilibrium): $$A + B \rightleftharpoons C$$ with eq

Designing a Controlled Kinetic Experiment

Design an experiment to determine the rate law for a reaction between reactants A and B. Your experi

Determining Overall Rate Law from a Multi-Step Reaction Mechanism

Consider the following multi-step mechanism for the conversion of A and B into product C: Step I (f

Determining Reaction Mechanism from Kinetic Data

Experimental studies of the reaction 2A + B → C yield a rate law of the form Rate = k [A]^2[B]. a.

Determining Reaction Order Using Initial Rates Method for $$2\text{A} + \text{B} \rightarrow \text{C}$$

The following experimental data was collected for the reaction $$2\text{A} + \text{B} \rightarrow \t

Determining Reaction Rate Laws from Experimental Data

A series of experiments were conducted to study the reaction $$A + 2*B + C \rightarrow D$$. Use the

Effect of Solvent Polarity on Reaction Kinetics

A reaction is performed in two different solvents: one polar and one non-polar. The measured rate co

Graphical Analysis of First-Order Kinetics

For a first-order reaction, the integrated rate law is given by $$\ln[A] = -k*t + \ln[A]_0$$. A grap

Influence of Surface Area on Reaction Kinetics in Heterogeneous Mixtures

Heterogeneous reactions often occur at the interface between phases. Answer the following parts rega

Integrated Rate Law for a Second-Order Reaction

For a reaction following second-order kinetics with respect to reactant A, the integrated rate law i

Investigating the Effect of Inhibitors on Reaction Kinetics

A reaction $$D \rightarrow E$$ is studied under two conditions: one without an inhibitor and one wit

Investigation of Kinetic Isotope Effects on Reaction Rates

An experiment is designed to compare the reaction rates of a compound and its deuterated analogue. A

Kinetic Data Analysis from Concentration vs Time Table

A series of experiments provided concentration data for reactant A over time. Analyze the data to de

Method of Initial Rates and Reaction Order Determination

Using the method of initial rates, the following experiments were conducted on a reaction involving

Pressure Effects on Gas-Phase Reaction Rates

In a gas-phase reaction study, the effect of reactant A's partial pressure on the reaction rate was

Pressure Effects on Gaseous Reaction Rates

A gas-phase reaction was studied at different pressures. The data below shows the observed reaction

Temperature Effects and the Arrhenius Equation

A series of experiments was conducted to study the effect of temperature on the rate constant of a r

Thermal Equilibration Neglect in Temperature-Dependent Kinetic Studies

An experiment was designed to measure reaction rate constants at various temperatures by rapidly hea

Application of Hess's Law in Sequential Reactions

A reaction pathway involves two sequential steps: Step 1 with \(\Delta H_1 = -30 \text{ kJ/mol}\) an

Applying Hess’s Law to Determine Reaction Enthalpy

Hess’s Law allows the calculation of reaction enthalpies by summing the known enthalpy changes of in

Bond Energy vs. Enthalpy of Formation Calculations

A report claims that calculating reaction enthalpy using bond energies yields the same result as usi

Calculating Reaction Enthalpy Using Bond Energies

Consider the reaction in which diatomic molecules A2 and B2 react to form 2 molecules of compound AB

Calorimetry: Determining Specific Heat

Calorimetry is used to determine the specific heat capacity of an unknown metal in an experimental s

Catalyst and Activation Energy

A researcher studies a reaction and observes that the addition of a catalyst lowers the activation e

Catalyst Impact on Activation Energy and Reaction Kinetics

A researcher studies a reaction both in the presence and absence of a catalyst. The reaction kinetic

Catalyst Recycling and Energy Savings in Industrial Processes

An industrial chemical process employs a catalyst to reduce the energy consumption of a reaction. Th

Chemical Reaction Calorimetry

In a bomb calorimeter experiment, 5.00 g of a substance is combusted, causing the temperature of a 1

Comparing Enthalpy of Fusion and Vaporization

Discuss the energetic requirements for phase transitions from solid to liquid (fusion) and liquid to

Comparing Exothermic and Endothermic Energy Diagrams

Two energy diagrams are provided: one representing an exothermic reaction and the other an endotherm

Determining Reaction Enthalpy Using Standard Enthalpy of Formation

Methanol (CH$_3$OH) is formed according to the reaction: $$C(s) + \frac{1}{2}O_2(g) + 2H_2(g) \right

Determining the Specific Heat of an Unknown Substance

A 50.0 g sample of an unknown metal is heated to 100°C and then quickly placed into a calorimeter co

Energy Profiles of Reversible Reactions

Analyze the energy diagram for a reversible reaction provided in the stimulus. The diagram shows bot

Energy Transfer in Redox Reactions of Rechargeable Batteries

Redox reactions in rechargeable batteries involve energy transfer that can result in measurable heat

Interpreting a Calorimetry Graph

A calorimetry experiment measuring a combustion reaction produced a temperature vs. time graph showi

Investigating the Effect of Temperature on Reaction Rate in Catalyzed Reactions

This question explores the influence of temperature on the rate of a catalyzed chemical reaction. Th

Kinetic Energy and Temperature in Gaseous Samples

A graph is provided showing how the average kinetic energy of gas molecules varies with temperature.

Light-Driven Photochemical Reactions and Thermodynamic Changes

Photochemical reactions absorb light energy, leading to unique thermodynamic changes. Explain the th

Phase Change and Spontaneity: Sublimation vs. Deposition

This FRQ explores the thermodynamics of phase changes, focusing on sublimation and deposition, and d

Phase Change Thermodynamics: Sublimation and Deposition

A substance undergoes sublimation, transitioning directly from a solid to a gas. An energy diagram i

Phase Diagram Analysis and Thermodynamics

A phase diagram for an unknown substance is provided, showing the boundaries between solid, liquid,

Real-World Application: Heat Transfer in Chemical Reactions

In certain laboratory reactions, observers note that a beaker can become noticeably hot during an ex

Study of Endothermic Dissolution Processes

An ionic salt dissolves in water through a multi-step process: Step 1: Breaking the ionic lattice (Δ

Thermodynamics in Phase Diagrams

Consider a phase diagram for a pure substance which displays the solid, liquid, and gas regions.

Advanced Equilibrium Analysis: Integrating Multiple Equilibrium Expressions

Consider a system with coupled equilibria: Reaction (1): $$A(aq) \rightleftharpoons B(aq)$$ with eq

Analyzing the Impact of Dilution on Reaction Equilibrium

Consider the equilibrium for carbonic acid formation: $$H_2CO_3(aq) \rightleftharpoons H^+(aq) + HC

Application of Hess's Law to Equilibrium Constant Manipulations

Consider the following reactions: Reaction 1: $$\text{A} \rightarrow \text{B}, \quad K_1 = 4.0$$ R

Application of Reaction Quotient (Q) in Determining Equilibrium Shift

For the reaction $$SO_2 + H_2O \leftrightharpoons H_2SO_3$$, answer the following parts.

Application of the Reaction Quotient (Q) Analysis

In a chemical system not initially at equilibrium, the reaction quotient (Q) can be used to predict

Calculation of the Reaction Quotient (Q)

For the reaction $$A + 2*B \rightleftharpoons 3*C$$, analyze the following concentration data provid

Concentration Effects in the Haber Process

The Haber synthesis reaction for ammonia is given by $$N_2(g)+3H_2(g) \rightleftharpoons 2NH_3(g)$$.

Conceptual Understanding of Reaction Quotient (Q)

Clarify the significance of the reaction quotient (Q) in chemical equilibrium and how it compares to

Designing an Experiment to Determine Keq

You are tasked with designing a laboratory experiment to determine the equilibrium constant (Kc) for

Designing an Experiment to Study Precipitation Using Ksp and Common Ion Effect

You aim to study the solubility of silver bromide (AgBr) by determining its $$K_{sp}$$. Design an ex

Determining the pH of a Weak Base Solution

A weak base B reacts with water according to the equilibrium $$B + H_2O \rightleftharpoons BH^+ + O

Determining the Solubility Product of AgCl

A researcher investigates the solubility of silver chloride (AgCl) in water. AgCl dissolves accordin

Dilution and $$K_a$$: Acetic Acid Equilibrium Experiment

A student investigates the ionization of acetic acid by preparing a 0.1 M solution and then diluting

Dilution Effects on Aqueous Equilibrium

Examine the equilibrium reaction: $$Fe^{3+}(aq) + SCN^{-}(aq) \leftrightarrow FeSCN^{2+}(aq)$$.

Dynamic Equilibrium and Reaction Rates

At equilibrium, a reaction exhibits constant concentrations due to balanced forward and reverse reac

Dynamics of Water Ionization and Determination of $$K_w$$

Design an experiment to measure the ionization of water and determine the value of the water ionizat

Effect of Catalysts on Equilibrium Dynamics

Investigations were conducted on the reaction D ⇌ E + F to compare the time required to reach equili

Effect of Concentration Changes on Equilibrium Shifts

Consider the equilibrium reaction $$PCl_5 \leftrightharpoons PCl_3 + Cl_2$$. Answer the following pa

Effect of Dilution on Aqueous Equilibria

Consider the equilibrium reaction: $$\mathrm{Fe^{3+} + SCN^{-} \rightleftharpoons FeSCN^{2+}}$$. Des

Equilibrium and pH Changes in Amphoteric Species

Certain metal ions in solution can exhibit amphoteric behavior, forming different complexes dependin

Equilibrium Concentration Calculations Using ICE Tables

Consider the reaction $$\text{N}_2 + 3*\text{H}_2 \leftrightharpoons 2*\text{NH}_3$$. Initially, 1.0

Equilibrium Constant Manipulations

For a given reaction, changes in the reaction equation can affect the equilibrium constant. Answer t

Equilibrium Constant Manipulations via Hess’s Law

Hess’s Law allows the manipulation of equilibrium constants for multi‐step reactions. Answer the fol

Equilibrium in Industrial Reaction Systems

Engineers study the equilibrium in the reaction: $$W(g) + 2X(g) \rightleftharpoons 3Y(g)$$ in an ind

Equilibrium Shifts in Response to External Stressors

Consider the equilibrium reaction: $$A + B \rightleftharpoons C + D$$. External changes in concentra

Experimental Design: Determining Ksp of a Sparingly Soluble Salt

Design an experiment to determine the solubility product constant (Ksp) of a sparingly soluble salt

Experimental Design: Determining the Acid Ionization Constant, Ka

A weak acid, HA, dissociates in water according to its equilibrium. Design an experiment to determin

Graphical Analysis of Equilibrium Approach

A graph showing the concentration versus time for a reversible reaction is provided. The graph displ

Haber Process Equilibrium Analysis

Consider the Haber process given by $$N_2 + 3*H_2 \leftrightharpoons 2*NH_3$$. This reaction is reve

Haber Process Reaction: Temperature and Pressure Effects

The Haber process for industrial ammonia synthesis is represented by the reaction $$N_2 + 3 * H_2 \r

Impact of Dilution on an Aqueous Equilibrium

An equilibrium system involving aqueous ions is represented by the reaction: $$Fe^{3+}(aq) + SCN^{-}

Impact of Dilution on Aqueous Equilibrium: The FeSCN2+ System

The equilibrium reaction for the formation of the colored complex ion is given by: $$Fe^{3+}(aq) + S

Impact of External Inert Gas Addition on Equilibria

Consider the equilibrium reaction: $$\ce{2A (g) <=> B (g)}$$. Investigate the effect of adding an in

Impact of Reaction Coefficient Scaling on Equilibrium Constants

Consider the reversible reaction: $$2*A + 3*B ⇌ 4*C$$ with an equilibrium constant $$K$$. A research

Investigating the Ionization Constant of Water (Kw)

Design an experiment to determine the ionization constant of water ($$K_w$$) by measuring $$[H^+]$$

Kinetics vs. Equilibrium Analysis

In a reaction experiment, it was observed that the reaction rate decreases over time until a constan

Le Chatelier's Principle and Pressure Changes

Examine the effects of pressure changes on a gaseous equilibrium system, particularly in systems wit

Le Chatelier's Principle in Coupled Equilibria

Consider a system where two equilibria are coupled as follows: (1) $$A \leftrightharpoons B$$ (2)

Manipulating Equilibrium Constants Using Hess's Law

Use Hess’s law to derive an overall equilibrium constant from a series of reactions and explain how

Manipulating Equilibrium Expressions Using Hess's Law

The following reactions are at equilibrium: (1) $$A \rightleftharpoons B$$ with $$K₁ = 4.0$$ (2) $$B

Manipulating Equilibrium with Hess’s Law

Explore how changes in the direction and stoichiometry of a reaction affect its equilibrium constant

Pressure Effects on Gaseous Equilibrium

Consider the gaseous equilibrium: $$\mathrm{N_2O_4 (g) \rightleftharpoons 2NO_2 (g)}$$. Answer the f

Reaction Quotient (Q) vs Equilibrium Constant (Keq)

For the reaction $$2H_2 (g) + O_2 (g) \rightleftharpoons 2*H_2O (g)$$, initial concentrations are gi

Reaction Quotient Analysis in a Perturbed System

For the reaction $$L + M \leftrightarrow N$$, initial concentrations are provided in the table below

Reaction Quotient and Equilibrium Dynamics

Consider the equilibrium reaction $$N_2 + 3 * H_2 \rightleftharpoons 2 * NH_3$$ under the initial co

Reaction Quotient and Equilibrium Prediction

A chemist monitors the progress of a reversible reaction and computes the reaction quotient, $$Q$$,

Reaction Quotient and Equilibrium Prediction

For the reaction $$2*A \leftrightarrow B + C$$, initial concentrations are provided in the table bel

Reaction Stoichiometry and Equilibrium

Consider the reaction: $$2A + B \rightleftharpoons 3C$$. Answer the following parts:

Role of Catalysts in Chemical Equilibrium

Explain the impact of catalysts on reaction rates and the position of chemical equilibrium in revers

Solubility Product and Common Ion Effect

Consider the sparingly soluble salt $$\rm AgCl(s) \rightleftharpoons Ag^{+}(aq) + Cl^{-}(aq)$$. Answ

Solubility Product and Common Ion Effect: Error Analysis

A researcher studies the solubility of AgCl by preparing solutions in pure water and in water contai

Temperature Dependence in Endothermic vs. Exothermic Reactions

Two reactions, one exothermic and one endothermic, were studied over a temperature range. Data table

Temperature Effects on Equilibrium Constants

Examine how temperature variations affect the equilibrium constants for both exothermic and endother

Temperature Effects on the Equilibrium Constant (Keq)

Experimental data for an exothermic reaction (similar to the Haber process) were collected at differ

Temperature Effects on the Haber Process

A researcher studies the impact of temperature on the reversible exothermic reaction of ammonia synt

The Common Ion Effect on Silver Chloride Solubility

A researcher studies the solubility of $$AgCl$$ in water and in a solution containing $$NaCl$$. Answ

Titration Error in Determining $$K_{sp}$$ of a Salt

A titration experiment is performed to determine the solubility product $$K_{sp}$$ for a sparingly s

Understanding Equilibrium in Reactions Involving Solids and Gases

Examine the equilibrium reaction: $$CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)$$ Answer the fol

Automated pH Meter Calibration and Verification

Accurate pH measurements are essential in acid-base experiments. Answer the following:

Buffer Capacity and Dilution Effects

A buffer system consisting of acetic acid and sodium acetate is under investigation to understand it

Buffer Solution pH Analysis

This FRQ addresses the behavior of buffer solutions by examining the relationship between the acid a

Buffer Solution: Acetic Acid and Sodium Acetate

A buffer solution is prepared by mixing acetic acid (HC2H3O2) and sodium acetate (NaC2H3O2), each at

Calculating pH Changes in a Buffer System Upon Addition of a Strong Acid

A buffer solution is prepared by mixing 0.25 M acetic acid (HC₂H₃O₂) with 0.25 M sodium acetate. The

Calculating pH in a Buffer using the Henderson-Hasselbalch Equation

A student prepares a buffer solution containing 0.1 M acetic acid and 0.1 M sodium acetate. Analyze

Common Ion Effect on Hydroxide Salt Solubility

Magnesium hydroxide, Mg(OH)₂, dissolves according to the equilibrium: $$Mg(OH)_2(s) \rightleftharpo

Comparative Acid Strengths: Binary vs. Oxoacids

Acid strength varies depending on molecular structure. Answer the following:

Designing a pH-Dependent Drug Release System

A pharmaceutical company is investigating a drug delivery system that releases medication when the p

Designing a Titration Experiment to Determine Weak Acid Concentration

This FRQ involves designing a titration experiment to determine the concentration of a weak acid usi

Determination of pH in a Dilute Strong Acid Solution

This FRQ focuses on determining the pH of a dilute strong acid solution by comparing calculated and

Determining pH of a Strong Acid Solution

An aqueous solution of a strong acid with $$[H^+] = 1.0\times10^{-3} \; M$$ is prepared. Answer the

Effect of Salt Addition on Buffer pH

A buffer solution composed of a weak acid and its conjugate base experiences the addition of a salt

Effects of Temperature on pH and Water Ionization

The autoionization of water is affected by temperature. Answer the following:

Influence of Temperature on the Ion Product of Water (Kw)

The ion product of water, $$K_w$$, is known to be temperature-dependent. Address the following issue

Le Châtelier's Principle in Weak Base Equilibrium

Examine the effect of adding a strong acid (HCl) to a weak base (ammonia) solution and how this impa

Misinterpretation in pH of Dilute Acid Solutions

A student prepared a very dilute hydrochloric acid solution (0.001 M) and calculated its pH using th

Neutralization Reaction Pathways

This FRQ compares the outcomes of different acid-base neutralization reactions using experimental da

pH Control in Industrial Chemical Reactions

Maintaining precise pH control is essential for many industrial reactions. Analyze how pH impacts re

Polyprotic Acid Dissociation Analysis

A researcher is studying a 0.1 M solution of phosphoric acid (H3PO4), a triprotic acid with the foll

Relationship Between $$K_a$$, $$K_b$$, and $$K_w$$

For a conjugate acid-base pair, the relationship $$K_a \times K_b = K_w$$ holds true. Given a weak a

Temperature Dependence of the Ion Product of Water

The ion product of water, $$K_w$$, is known to vary with temperature. Consider the experimental data

Temperature-Dependent pH Variation: Neglecting Kw Variation

A student measured the pH of pure water at various temperatures to study its temperature dependence.

Weak Acid Dissociation and Percent Ionization

The percent dissociation of a weak acid gives insight into its strength and ionization behavior in s

Weak Acid pH Calculation and Percent Dissociation

A researcher is investigating the pH of a weak acid solution. The solution is 0.1 M acetic acid (HC2

Weak Acid-Strong Base Titration Analysis

A titration is performed by titrating 30.0 mL of 0.10 M acetic acid (HC2H3O2) with 0.10 M NaOH. The

Analyzing a Voltaic Cell's Performance Over Time

A report claims that the voltage output of a voltaic cell remains constant over several hours of ope

Connecting Reduction Potentials and Gibbs Free Energy

For the copper half-reaction: $$Cu^{2+} + 2e^- -> Cu$$ with a standard reduction potential of +0.34

Designing a Galvanic Cell

A galvanic cell is constructed using a copper electrode immersed in 1 M CuSO₄ and a zinc electrode i

Designing an Experiment for Electroplating Efficiency

An engineer designs an electrolytic cell to study the efficiency of electroplating a metal. The goal

Designing an Experiment to Measure Gibbs Free Energy Change using a Galvanic Cell

Design a controlled experiment to determine the standard Gibbs free energy change $$\Delta G^\circ$$

Determination of Equilibrium Constant from Gibbs Free Energy

A study claims that the equilibrium constant (K) for a reaction can be directly calculated using the

Electroplating Efficiency and Calculations

Electroplating is a common industrial application of electrolytic cells. Analyze the process with th

Entropy Changes in Metabolic Reactions

Glycolysis, the metabolic pathway converting glucose to pyruvate, involves multiple steps that produ

Equilibrium Constant and Free Energy Connection

A redox reaction exhibits a standard cell potential of $$E^\circ_{cell} = 0.50\,V$$ with 2 moles of

Evaluating Electrolysis Efficiency

An electroplating experiment operating at a current of 5.00 A for 2 hours resulted in 10.0 g of meta

Evaluating Reaction Conditions for Electrolysis

An electrolytic cell is used to decompose water with a constant current of $$1.5\,A$$ applied for $$

FRQ 3: Galvanic Cell Voltage and Reaction Quotient

A galvanic cell operating under non‐standard conditions is described by the Nernst equation: $$E =

FRQ 11: Relating Equilibrium Constants to Cell Potentials

A certain redox reaction in a galvanic cell involves an exchange of \(n = 3\) electrons and has a st

Gibbs Free Energy and Equilibrium Constant

Using the relationship $$\Delta G^\circ = -R*T \ln K$$, where R = $$8.31\,J/(mol\cdot K)$$ and T = 2

Measuring Gibbs Free Energy via Electrochemical Cells

A group of students assembles a galvanic cell to measure its open-circuit potential and determine th

Pressure Effects on Gibbs Free Energy

In gas-phase reactions, pressure changes can influence the Gibbs free energy. Consider a reaction th

Reaction Entropy Change Analysis

In a laboratory, you are given the reaction: $$2*A(g) + B(l) \rightarrow 3*C(g) + D(s)$$. Refer to t

Redox Titration and Free Energy

A laboratory experiment involves a redox titration using a galvanic cell to determine the concentrat

Reduction Potential and Overall Redox Reaction

Analyze the overall redox reaction using provided half-reactions and discuss the implications of ele

Reduction Potential Driven Driving Force

A paper suggests that the spontaneity of redox reactions can be completely predicted by measured red

Relating Equilibrium Constant and Free Energy

For a particular reaction at 298 K, the equilibrium constant (K) is measured to be 55. Use the relat

Temperature Dependence of Equilibrium in Redox Reactions

Experimental data for a redox reaction is provided below.

Temperature Dependence of Gibbs Free Energy

For a reaction described by the equation $$\Delta G° = \Delta H° - T\Delta S°$$, analyze how tempera

Temperature’s Effect on Gibbs Free Energy

Consider a reaction with $$\Delta H^\circ = 60\,kJ/mol$$ and $$\Delta S^\circ = 150\,J/(mol\cdot K)$

Thermodynamic vs Kinetic Control in Reactions

Some reactions exhibit a negative \(\Delta G°\) (thermodynamically favored) but proceed very slowly