200+ Free Praxis General Science Practice Questions

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In an experiment testing whether fertilizer affects bean plant height, what is the independent variable?

The final height of the plants

The amount of fertilizer applied

The species of plant used

The amount of sunlight received

to track

2026 Statistics

Key Facts: Praxis General Science Exam

135

Selected-Response Questions

ETS General Science (5436) test page

2h 30m

Testing Time

ETS General Science (5436) test page / study companion

$130

Current Fee Tier

ETS Praxis Subject Assessment pricing

11 / 31 / 33 / 25

Official Domain Weighting

ETS General Science study companion

5436 live / 5435 practice

Current Code Context

Official ETS test page and practice test page

Daily

2025-2026 Availability

ETS Praxis availability PDFs

For 2026 planning, ETS currently lists the live General Science exam as test code 5436 with 135 selected-response questions in 2 hours and 30 minutes at the $130 Praxis Subject Assessment fee tier. ETS also continues to offer an official practice test labeled General Science: Content Knowledge (5435), so candidates may encounter both codes in 2026 prep. The official study companion weights the blueprint 11% Nature and Impact of Science and Engineering, 31% Physical Science, 33% Life Science, and 25% Earth and Space Science. As of March 7, 2026, I did not find an official ETS notice announcing a nationwide redesign or replacement of the current science blueprint.

Sample Praxis General Science Practice Questions

Try these sample questions to test your Praxis General Science exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 200+ question experience with AI tutoring.

1In an experiment testing whether fertilizer affects bean plant height, what is the independent variable?

A.The final height of the plants

B.The amount of fertilizer applied

C.The species of plant used

D.The amount of sunlight received

Explanation: The independent variable is the factor deliberately changed by the investigator. In this experiment, the researcher changes the amount of fertilizer and then measures plant height as the response.

2Why is a control group important in a well-designed scientific experiment?

A.It guarantees the hypothesis will be supported

B.It provides a baseline for comparison

C.It increases the number of independent variables

D.It removes the need for repeated trials

Explanation: A control group provides a baseline so the effect of the tested variable can be compared against a standard condition. Without a control, it is much harder to determine whether the treatment actually caused the observed change.

3A balance consistently gives a mass reading of 50.2 g for a sample whose accepted mass is 49.8 g. Which statement best describes the measurements?

A.They are accurate but not precise

B.They are precise but not accurate

C.They are both accurate and precise

D.They are neither accurate nor precise

Explanation: Precision refers to consistency among repeated measurements, while accuracy refers to closeness to the accepted value. Because the balance repeatedly gives nearly the same reading but that reading is off from the accepted mass, the results are precise but not accurate.

4A graph shows that as the temperature of water increases from 20°C to 80°C, the amount of dissolved sugar also increases. Which conclusion is best supported by the graph?

A.Sugar is the only substance whose solubility changes with temperature

B.Increasing temperature can increase the solubility of sugar in water

C.Heating water creates sugar through a chemical reaction

D.Water must reach its boiling point before sugar can dissolve

Explanation: The graph supports the conclusion that higher water temperature can increase sugar solubility. It does not justify broader claims about all substances, chemical creation of sugar, or the need to reach boiling.

5Which lab safety procedure is correct when diluting a strong acid?

A.Pour water into the acid slowly

B.Mix the acid and water in a sealed container

C.Add the acid to water slowly

D.Heat the acid first to reduce splashing

Explanation: The safe rule is to add acid to water slowly. This reduces the risk of sudden boiling and splattering caused by the heat released during dilution.

6A team is designing a low-cost water filter for disaster relief. The filter works very well but is too expensive for large-scale use. What is the best next engineering step?

A.Adopt the design immediately because performance is more important than cost

B.Ignore the cost because engineering only concerns whether something works

C.Revise the design to balance effectiveness with cost constraints

D.Discard all data from the prototype because the first design failed to meet every goal

Explanation: Engineering design requires balancing criteria and constraints, not maximizing a single feature in isolation. If the filter is effective but too expensive, the next step is to revise the design so it better meets both performance and cost goals.

7What does the atomic number of an element represent?

A.The number of neutrons in the nucleus

B.The number of protons in the nucleus

C.The total number of protons and neutrons

D.The number of electron shells

Explanation: The atomic number is defined as the number of protons in an atom’s nucleus. Because each element has a unique number of protons, the atomic number identifies the element.

8Two atoms of carbon both have 6 protons, but one has 6 neutrons and the other has 8 neutrons. These two atoms are:

A.Ions

B.Isotopes

C.Compounds

D.Allotropes

Explanation: Atoms of the same element that differ in neutron number are isotopes. They have the same atomic number because they contain the same number of protons, but they have different mass numbers.

9Which substance is most likely to contain ionic bonds?

A.Carbon dioxide (CO2)

B.Sodium chloride (NaCl)

C.Methane (CH4)

D.Water (H2O)

Explanation: Ionic bonds commonly form between a metal and a nonmetal through electron transfer. Sodium chloride fits that pattern because sodium loses an electron and chlorine gains one, creating oppositely charged ions that attract.

10Why must the same number of each type of atom appear on both sides of a balanced chemical equation?

A.Because atoms are destroyed during chemical reactions

B.Because mass is conserved in chemical reactions

C.Because balanced equations always have equal numbers of molecules on both sides

D.Because electrons cannot move between atoms during reactions

Explanation: Balanced equations reflect the law of conservation of mass: atoms are rearranged during a chemical reaction but are not created or destroyed. The count of each element must therefore remain the same on both sides of the equation.

About the Praxis General Science Exam

Praxis General Science Content Knowledge (5435) is the broad-field secondary science teacher-certification practice bank on this site. It is aligned to the current ETS General Science blueprint, which ETS currently lists under operational test code 5436 and weights across nature and impact of science and engineering, physical science, life science, and earth and space science.

Questions

135 scored questions

Time Limit

2h 30m

Passing Score

Varies by state or agency

Exam Fee

$130 (ETS / Praxis)

Praxis General Science Exam Content Outline

11%

Nature and Impact of Science and Engineering

Scientific inquiry, evidence, experimental design, measurement, graphing, lab safety, the history and nature of science, engineering design, and the role of science and technology in society.

31%

Physical Science

Matter and atomic structure, bonding and reactions, solutions, acids and bases, energy, forces and motion, waves, sound, light, electricity, magnetism, and related quantitative reasoning.

33%

Life Science

Cells, metabolism, genetics, heredity, evolution, ecology, biodiversity, and human body systems with a strong emphasis on processes and relationships rather than isolated vocabulary.

25%

Earth and Space Science

Plate tectonics, geologic processes, rocks and geologic time, weather and climate, atmosphere and oceans, the water cycle, Earth motions, the solar system, stars, galaxies, and the universe.

How to Pass the Praxis General Science Exam

What You Need to Know

Passing score: Varies by state or agency
Exam length: 135 questions
Time limit: 2h 30m
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 General Science Study Tips from Top Performers

1Weight your study time by the official blueprint: life science first, physical science second, Earth and space science third, and inquiry and engineering as a regular but smaller review block.

2Treat science-inquiry questions as evidence questions: identify the variable, the control, the measurement, and what conclusion the data actually supports before choosing an answer.

3In chemistry and physics, write down the core relationship first, such as conservation of mass, density, pH, Newtonian force relations, or wave-frequency-energy links, before doing option elimination.

4For life science, connect structure to function and process to outcome, especially in cell transport, genetics, evolution, ecology, and homeostasis.

5In Earth and space science, anchor your reasoning to systems: plate interactions, rock-cycle transitions, energy transfer in the atmosphere-ocean system, and Earth-sun-moon geometry.

Frequently Asked Questions

Is Praxis General Science 5435 the same as 5436?

In current official ETS materials, the live operational test page is listed as General Science (5436), while ETS still sells an official practice test titled General Science: Content Knowledge (5435). For practical prep, the safest approach is to study the current 5436 blueprint and confirm with your state or program which code they reference.

How many questions are on Praxis General Science and how long is it?

ETS currently lists the live General Science exam as 135 selected-response questions in 2 hours and 30 minutes. That gives you less than 70 seconds per item on average, so pacing matters even though many questions are concept-based rather than computation-heavy.

What content matters most on Praxis General Science?

Use the official weighting as your study plan: Life Science is largest at 33%, Physical Science is 31%, Earth and Space Science is 25%, and Nature and Impact of Science and Engineering is 11%. In practice, that means almost two thirds of your time should go to life and physical science, but you still need dependable Earth and space coverage because one quarter of the exam sits there.

What passing score do I need?

Praxis passing scores are set by states, agencies, and educator-preparation programs rather than by one universal ETS cutoff. ETS points candidates to the state requirements lookup, so confirm your exact score requirement before registering or sending score reports.

How much does Praxis General Science cost?

The current ETS test page lists General Science in the selected-response Praxis Subject Assessment fee tier, which is $130. Always confirm the live total in your ETS account before checkout in case ETS updates taxes, service fees, or bundled offers.

What changed for Praxis General Science in 2026?

As of March 7, 2026, I did not find an official ETS notice announcing a nationwide redesign, new cut-score policy, or replacement code for the current General Science blueprint. The notable current context is simply that ETS uses 5436 on the live test page while an official practice product still uses 5435, so you may see both numbers in prep materials.

How should I study for Praxis General Science efficiently?

Study by blueprint weight and by weakness. Start with life science and physical science, then review Earth and space science, and finish with inquiry, lab methods, and engineering-design scenarios. Mixed timed sets matter because the exam expects you to switch quickly across biology, chemistry, physics, geology, and astronomy without losing precision.