Career upgrade: Learn practical AI skills for better jobs and higher pay.
Level up
PracticeVideosBlogFlashcardsEspañol
All Practice Exams

100+ Free Praxis Chemistry 5245 Practice Questions

Pass your Praxis Chemistry Content Knowledge (5245) exam on the first try — instant access, no signup required.

✓ No registration✓ No credit card✓ No hidden fees✓ Start practicing immediately
100+ Questions
100% Free
1 / 100
Question 1
Score: 0/0

Which element is the most electronegative?

A
B
C
D
to track
Same family resources

Explore More Praxis Exams

Continue into nearby exams from the same family. Each card keeps practice questions, study guides, flashcards, videos, and articles in one place.

Praxis Core

Practice QuestionsStudy GuideFlashcards3 videos4 blogs

Praxis Elementary

Practice QuestionsStudy GuideCheat SheetFlashcards1 video1 blog

Praxis Biology

Practice QuestionsCheat SheetFlashcards1 blog

Praxis English Language Arts 5038

Practice Questions1 video1 blog

Praxis English to Speakers of Other Languages (ESOL)

Practice Questions1 blog

Praxis Speech-Language Pathology

Practice Questions1 video1 blog

More From This Family

Videos and articles for deeper review.

VideoFREE Praxis 5038 ELA Exam Guide 2026: Pass Content Knowledge First TryVideoFREE Praxis Core Study Guide 2026: Pass Your Teacher Certification ExamVideoFREE Praxis Elementary Education (5001) Exam Guide 2026: Complete Study GuideVideoFREE Praxis Elementary Education (5001) Exam Guide 2026: Complete Study GuideArticlePraxis Chemistry 5246 Exam Guide 2026: What Chemistry Teachers Should Study13 min readArticleFREE Praxis 5038 ELA Exam Guide 2026: Pass Content Knowledge First Try15 min readArticleFREE Praxis Biology 5236 Exam Guide 2026: ETS Format, Topics, Study Plan13 min readArticleFREE Praxis Core Study Guide 2026: Pass Your Teacher Certification Exam15 min read
2026 Statistics

Key Facts: Praxis Chemistry 5245 Exam

125

Selected-Response Questions

ETS Praxis 5245 Study Companion

2h 30m

Testing Time

ETS Praxis 5245 Study Companion

$130

Current Exam Fee

ETS Praxis Website

20%

Largest Domain (Reactions/Periodicity)

ETS Praxis 5245 Study Companion

For 2026, the Praxis 5245 is a 125-question, 2.5-hour computer-delivered selected-response exam priced at $130. The official study companion weights the exam across seven domains: Matter/Thermodynamics 14%, Atomic Structure 12%, Bonding/Structure 15%, Reactions/Periodicity 20%, Solutions/Acid-Base 15%, Scientific Inquiry 12%, and Procedures 12%.

Sample Praxis Chemistry 5245 Practice Questions

Try these sample questions to test your Praxis Chemistry 5245 exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1A student heats a mixture of iron filings and sulfur powder. After heating, the resulting substance cannot be separated by a magnet. What type of change occurred?
A.A physical change because the appearance changed
B.A chemical change because a new substance with different properties formed
C.A physical change because heating is always a physical process
D.A nuclear change because heat energy was involved
Explanation: When iron and sulfur are heated together, they undergo a chemical reaction to form iron sulfide, a new compound with properties different from either reactant. The fact that a magnet can no longer separate the iron indicates a new substance formed, which is the hallmark of a chemical change.
2Which of the following is an intensive property of matter?
A.Mass
B.Volume
C.Density
D.Length
Explanation: Density is an intensive property because it does not depend on the amount of substance present. A small sample of gold has the same density as a large sample of gold. Intensive properties are useful for identifying substances because they remain constant regardless of sample size.
3A 50.0 g sample of metal at 95.0°C is placed into 100.0 g of water at 25.0°C. The final temperature of the system is 28.5°C. What is the specific heat of the metal? (Specific heat of water = 4.184 J/g·°C)
A.0.44 J/g·°C
B.0.13 J/g·°C
C.0.88 J/g·°C
D.1.46 J/g·°C
Explanation: Using q = mcΔT, the heat gained by water equals the heat lost by the metal. q_water = 100.0 × 4.184 × (28.5 − 25.0) = 1464.4 J. For the metal: 1464.4 = 50.0 × c × (95.0 − 28.5), so c = 1464.4 / (50.0 × 66.5) = 0.44 J/g·°C.
4At standard pressure, which phase change releases energy?
A.Melting
B.Evaporation
C.Sublimation
D.Condensation
Explanation: Condensation is the phase change from gas to liquid. During this process, intermolecular forces form between gas molecules as they slow down, releasing kinetic energy as heat to the surroundings. All phase changes that increase intermolecular interactions (condensation, freezing, deposition) are exothermic.
5According to the kinetic molecular theory, which assumption is true for an ideal gas?
A.Gas particles exert attractive forces on each other
B.Gas particles have a volume that is significant relative to the container
C.The average kinetic energy of gas particles is proportional to absolute temperature
D.Collisions between gas particles are inelastic
Explanation: The kinetic molecular theory states that the average kinetic energy of gas particles is directly proportional to the absolute temperature (in Kelvin). This means at higher temperatures, gas particles move faster on average. The theory also assumes negligible particle volume, no intermolecular forces, and perfectly elastic collisions.
6A gas occupies 2.0 L at 300 K and 1.0 atm. What volume will it occupy at 600 K and 1.0 atm?
A.1.0 L
B.4.0 L
C.2.0 L
D.6.0 L
Explanation: At constant pressure, Charles's Law states V₁/T₁ = V₂/T₂. Substituting: 2.0/300 = V₂/600, so V₂ = 2.0 × 600/300 = 4.0 L. Doubling the absolute temperature at constant pressure doubles the volume.
7Using Hess's Law, if Reaction 1 has ΔH = −200 kJ and Reaction 2 has ΔH = +50 kJ, what is the overall enthalpy change when both reactions occur in sequence?
A.−250 kJ
B.−150 kJ
C.+150 kJ
D.+250 kJ
Explanation: Hess's Law states that the total enthalpy change for a process is the sum of the enthalpy changes of the individual steps. ΔH_total = (−200) + (+50) = −150 kJ. The overall reaction is exothermic because the net energy released exceeds the energy absorbed.
8On a heating curve, what occurs during the flat (plateau) regions where temperature remains constant despite continued heating?
A.The substance is increasing in temperature within a single phase
B.A phase change is occurring, and the added energy is overcoming intermolecular forces
C.The substance has reached thermal equilibrium with the surroundings
D.Chemical bonds within molecules are breaking
Explanation: During a phase change (melting or boiling), added heat energy is used to overcome intermolecular forces rather than to increase kinetic energy of the particles. This is why the temperature remains constant on the plateau regions of a heating curve. The energy absorbed during these transitions is the heat of fusion or heat of vaporization.
9A sample of gas at 2.0 atm and 4.0 L is compressed to 1.0 L at constant temperature. What is the new pressure?
A.0.5 atm
B.2.0 atm
C.4.0 atm
D.8.0 atm
Explanation: Using Boyle's Law (P₁V₁ = P₂V₂) at constant temperature: 2.0 × 4.0 = P₂ × 1.0, so P₂ = 8.0 atm. When volume decreases, pressure increases proportionally at constant temperature.
10Which statement correctly describes an endothermic reaction?
A.The products have lower enthalpy than the reactants
B.The surroundings increase in temperature
C.The system absorbs heat from the surroundings, and ΔH is positive
D.Bond formation releases more energy than bond breaking requires
Explanation: In an endothermic reaction, the system absorbs energy from the surroundings to break bonds that are stronger than the bonds formed in the products. The enthalpy of the products is higher than the reactants, so ΔH is positive. The surroundings cool down as energy flows into the reacting system.

About the Praxis Chemistry 5245 Exam

Praxis Chemistry Content Knowledge (5245) is the ETS subject assessment for secondary chemistry teacher certification. This practice bank covers all seven official domains: matter and energy, atomic structure, bonding, chemical reactions, solutions and acid-base chemistry, scientific inquiry, and laboratory procedures.

Questions

125 scored questions

Time Limit

2 hours 30 minutes

Passing Score

Varies by state (typically 135-160)

Exam Fee

$130 (ETS / Praxis)

Praxis Chemistry 5245 Exam Content Outline

14%

Basic Principles of Matter and Energy; Thermodynamics

States of matter, phase transitions, kinetic molecular theory, gas laws, calorimetry, enthalpy, Hess's Law, and entropy.

12%

Atomic and Nuclear Structure

Subatomic particles, electron configurations, quantum numbers, atomic spectra, periodic trends, radioactive decay, and nuclear reactions.

15%

Nomenclature; Chemical Composition; Bonding and Structure

IUPAC naming, empirical and molecular formulas, ionic and covalent bonding, Lewis structures, VSEPR, hybridization, and intermolecular forces.

20%

Chemical Reactions; Periodicity

Balancing equations, stoichiometry, reaction types, oxidation-reduction, reaction rates, equilibrium, Le Chatelier's principle, and periodic trends.

15%

Solutions and Solubility; Acid-Base Chemistry

Concentration units, colligative properties, solubility, acid-base definitions, pH, buffers, titrations, and solubility product.

12%

Scientific Inquiry and Social Perspectives of Science

Scientific method, experimental design, history of chemistry, science-technology-society connections, and chemistry in daily life.

12%

Scientific Procedures and Techniques

Significant figures, unit conversions, laboratory equipment, safety procedures, separation techniques, error analysis, and data reporting.

How to Pass the Praxis Chemistry 5245 Exam

What You Need to Know

  • Passing score: Varies by state (typically 135-160)
  • Exam length: 125 questions
  • Time limit: 2 hours 30 minutes
  • Exam fee: $130

Keys to Passing

  • Complete 500+ practice questions
  • Score 80%+ consistently before scheduling
  • Focus on highest-weighted sections
  • Use our AI tutor for tough concepts

Praxis Chemistry 5245 Study Tips from Top Performers

1Prioritize Chemical Reactions and Periodicity (20% of the exam) — master stoichiometry, equilibrium, and redox reactions.
2Practice solving quantitative problems: gas laws, pH calculations, molarity, and calorimetry appear frequently.
3Review VSEPR theory and Lewis structures thoroughly, as bonding and molecular geometry questions are common.
4Know the periodic trends (atomic radius, ionization energy, electronegativity) and be able to explain the underlying reasons.
5Familiarize yourself with laboratory safety rules, equipment names, and separation techniques for the procedures section.

Frequently Asked Questions

How many questions are on the Praxis Chemistry exam (5245)?

The Praxis Chemistry Content Knowledge exam has 125 selected-response questions to be completed in 2 hours and 30 minutes.

What is a passing score on the Praxis Chemistry 5245 exam?

Passing scores are set by each state and typically range from 135 to 160. Check the ETS state requirements page for your specific state's passing score.

What content is covered on the Praxis Chemistry 5245 exam?

The exam covers seven content areas: Basic Principles of Matter and Energy (14%), Atomic and Nuclear Structure (12%), Nomenclature, Bonding, and Structure (15%), Chemical Reactions and Periodicity (20%), Solutions and Acid-Base Chemistry (15%), Scientific Inquiry (12%), and Scientific Procedures (12%).

Is the Praxis 5245 being replaced by the 5246?

Some states have transitioned to the Praxis Chemistry 5246. Check your state's current requirements on the ETS website, as requirements vary by state and may have changed.