Are flashcards effective for the Praxis 5435?

Yes. Flashcards use active recall — retrieving an answer from memory — which research shows is one of the most effective study methods, especially in short, spaced sessions. Because the 5435 rewards instant recall of science facts, formulas, and vocabulary across four subjects, the cards are an efficient way to make that knowledge automatic.

What topics do the Praxis 5435 flashcards cover?

All four content categories: the nature of science (scientific method, measurement, engineering), Physical Science (atoms, the periodic table, reactions, forces, energy, waves, electricity), Life Science (cells, genetics, evolution, ecology), and Earth and Space Science (geology, the atmosphere, weather, and astronomy).

How should I study with these Praxis 5435 flashcards?

Lead with the highest-weighted category — Physical Science is roughly a third of the test — then Life Science and Earth and Space Science. Mix the modes: flip to learn, type to test recall, match for speed, and quiz to check yourself before working full practice questions, and give extra time to whichever science you studied least.

Are the Praxis 5435 flashcards free?

Yes — 100% free, all four study modes, no paywall.

Do these flashcards match the current Praxis 5435 test?

Yes. The cards are organized to the ETS content categories for the Praxis General Science: Content Knowledge (5435) and cover the introductory physics, chemistry, biology, and earth and space science the exam samples across its roughly 135 questions.

The factor a researcher deliberately changes to test its effect; plotted on the x-axis as the suspected cause.

The outcome that is measured; it depends on (responds to) the independent variable and is plotted on the y-axis.

Controlled variable (constant)

A condition kept the same across all groups so it cannot influence the results.

The group that does not receive the experimental treatment; it provides a baseline for comparison.

A testable, falsifiable, proposed explanation, often stated as an 'if/then' prediction about how variables relate.

A claim is falsifiable if there is a possible observation or experiment that could prove it wrong; a requirement for a scientific hypothesis.

A broad, well-substantiated explanation supported by a large body of evidence (e.g., evolution, plate tectonics) — far stronger than a guess.

A statement (often mathematical) describing a consistent natural pattern, such as Newton's laws; it describes what happens but not why.

Accuracy vs. precision

Accuracy = closeness to the true value; precision = closeness of repeated measurements to each other. Measurements can be precise but inaccurate.

A consistent error that shifts every measurement in the same direction (e.g., a balance reading high), reducing accuracy but not precision.

Unpredictable scatter in measurements from trial to trial; reduced by averaging many trials.

Independent vs. dependent on a graph

Independent (manipulated) variable goes on the x-axis; dependent (measured/responding) variable goes on the y-axis.

Repeating an experiment to confirm results are reliable and not due to chance; central to the self-correcting nature of science.

Evaluation of research by independent experts before publication; a key check on the quality and validity of scientific claims.

Observation vs. inference

An observation is information gathered directly with the senses or instruments; an inference is a conclusion drawn from observations.

Qualitative vs. quantitative data

Qualitative = descriptive (color, texture); quantitative = numerical/measured (mass, length, time).

Meter (length), kilogram (mass), second (time), kelvin (temperature), ampere (current), mole (amount), candela (luminous intensity).

Independent variable, one at a time

A valid controlled experiment changes only one independent variable so any change in the outcome can be attributed to it.

Scientific method (iterative)

Question → hypothesis → experiment → analyze data → conclusion; results often loop back to new questions, so it is iterative, not one-time.

Correlation vs. causation

Two variables changing together (correlation) does not prove one causes the other; only a controlled experiment can establish causation.

A simplified representation (physical, mathematical, or conceptual) used to explain or predict phenomena, e.g., the atomic model.

Lab safety: chemical splash

Always wear goggles; flush eyes/skin with water for 15 minutes and notify the instructor if a chemical contacts them.

Engineering design process

Define the problem and constraints → brainstorm → design → build a prototype → test → evaluate → redesign (iterate).

Science vs. engineering

Science seeks to understand the natural world; engineering applies that understanding to design solutions under real-world constraints.

Technology and society

Scientific and engineering advances shape society (medicine, energy, communication) and raise ethical, economic, and environmental questions.

The digits in a measurement that carry meaning about its precision; the result of a calculation should reflect the least precise measurement.

Mean = average; median = middle value of ordered data; mode = most frequent value. The median resists outliers.

Constraint (engineering)

A limit on a design solution, such as cost, time, materials, safety, or available space.

Information acquired through observation or experiment; the basis for testing scientific claims.

Claims presented as scientific but lacking testability, falsifiability, or supporting evidence (e.g., astrology).

Proton, neutron, electron

Protons (+, in nucleus), neutrons (neutral, in nucleus), electrons (−, orbit nucleus). Nearly all the atom's mass is in the nucleus.

The number of protons in an atom; it defines the element's identity.

The sum of protons and neutrons in an atom's nucleus.

Atoms of the same element (same protons) with different numbers of neutrons, and thus different mass numbers.

An atom that has gained or lost electrons, giving it a net negative (anion) or positive (cation) charge.

Periodic table groups

Columns of elements with similar chemical properties because they have the same number of valence electrons.

Periodic table periods

Horizontal rows; properties change gradually from left (metals) to right (nonmetals) across a period.

Generally decreases left-to-right across a period (more nuclear charge pulls electrons in) and increases down a group.

Electronegativity trend

Increases up and to the right; fluorine is the most electronegative element.

The energy required to remove an electron from a neutral atom; increases left-to-right across a period.

Electrons in the outermost shell; they determine an element's bonding behavior and reactivity.

A bond formed by the transfer of electrons from a metal to a nonmetal, producing oppositely charged ions that attract.

A bond formed when two nonmetal atoms share electrons.

Bonding in metals where positive ions sit in a 'sea' of delocalized electrons, explaining conductivity and malleability.

Law of conservation of mass

Mass is neither created nor destroyed in a chemical reaction; the mass of reactants equals the mass of products.

Your FREE Praxis 5435 Flashcards 2026 – 200+ Cards

Realistic, Praxis 5435-style flashcards across all four content categories — flip, match, type, and quiz yourself.

How well do you know them?

Praxis 5435 Flashcards

Independent variable: The factor a researcher deliberately changes to test its effect; plotted on the x-axis as the suspected cause.
Dependent variable: The outcome that is measured; it depends on (responds to) the independent variable and is plotted on the y-axis.
Controlled variable (constant): A condition kept the same across all groups so it cannot influence the results.
Control group: The group that does not receive the experimental treatment; it provides a baseline for comparison.
Hypothesis: A testable, falsifiable, proposed explanation, often stated as an 'if/then' prediction about how variables relate.
Falsifiable: A claim is falsifiable if there is a possible observation or experiment that could prove it wrong; a requirement for a scientific hypothesis.
Scientific theory: A broad, well-substantiated explanation supported by a large body of evidence (e.g., evolution, plate tectonics) — far stronger than a guess.
Scientific law: A statement (often mathematical) describing a consistent natural pattern, such as Newton's laws; it describes what happens but not why.
Accuracy vs. precision: Accuracy = closeness to the true value; precision = closeness of repeated measurements to each other. Measurements can be precise but inaccurate.
Systematic error: A consistent error that shifts every measurement in the same direction (e.g., a balance reading high), reducing accuracy but not precision.
Random error: Unpredictable scatter in measurements from trial to trial; reduced by averaging many trials.
Independent vs. dependent on a graph: Independent (manipulated) variable goes on the x-axis; dependent (measured/responding) variable goes on the y-axis.
Replication: Repeating an experiment to confirm results are reliable and not due to chance; central to the self-correcting nature of science.
Peer review: Evaluation of research by independent experts before publication; a key check on the quality and validity of scientific claims.
Observation vs. inference: An observation is information gathered directly with the senses or instruments; an inference is a conclusion drawn from observations.
Qualitative vs. quantitative data: Qualitative = descriptive (color, texture); quantitative = numerical/measured (mass, length, time).
SI base units: Meter (length), kilogram (mass), second (time), kelvin (temperature), ampere (current), mole (amount), candela (luminous intensity).
Independent variable, one at a time: A valid controlled experiment changes only one independent variable so any change in the outcome can be attributed to it.
Scientific method (iterative): Question → hypothesis → experiment → analyze data → conclusion; results often loop back to new questions, so it is iterative, not one-time.
Correlation vs. causation: Two variables changing together (correlation) does not prove one causes the other; only a controlled experiment can establish causation.
Model (in science): A simplified representation (physical, mathematical, or conceptual) used to explain or predict phenomena, e.g., the atomic model.
Lab safety: chemical splash: Always wear goggles; flush eyes/skin with water for 15 minutes and notify the instructor if a chemical contacts them.
Engineering design process: Define the problem and constraints → brainstorm → design → build a prototype → test → evaluate → redesign (iterate).
Science vs. engineering: Science seeks to understand the natural world; engineering applies that understanding to design solutions under real-world constraints.
Technology and society: Scientific and engineering advances shape society (medicine, energy, communication) and raise ethical, economic, and environmental questions.
Significant figures: The digits in a measurement that carry meaning about its precision; the result of a calculation should reflect the least precise measurement.
Mean, median, mode: Mean = average; median = middle value of ordered data; mode = most frequent value. The median resists outliers.
Constraint (engineering): A limit on a design solution, such as cost, time, materials, safety, or available space.
Empirical evidence: Information acquired through observation or experiment; the basis for testing scientific claims.
Pseudoscience: Claims presented as scientific but lacking testability, falsifiability, or supporting evidence (e.g., astrology).
Proton, neutron, electron: Protons (+, in nucleus), neutrons (neutral, in nucleus), electrons (−, orbit nucleus). Nearly all the atom's mass is in the nucleus.
Atomic number: The number of protons in an atom; it defines the element's identity.
Mass number: The sum of protons and neutrons in an atom's nucleus.
Isotopes: Atoms of the same element (same protons) with different numbers of neutrons, and thus different mass numbers.
Ion: An atom that has gained or lost electrons, giving it a net negative (anion) or positive (cation) charge.
Periodic table groups: Columns of elements with similar chemical properties because they have the same number of valence electrons.
Periodic table periods: Horizontal rows; properties change gradually from left (metals) to right (nonmetals) across a period.
Atomic radius trend: Generally decreases left-to-right across a period (more nuclear charge pulls electrons in) and increases down a group.
Electronegativity trend: Increases up and to the right; fluorine is the most electronegative element.
Ionization energy: The energy required to remove an electron from a neutral atom; increases left-to-right across a period.
Valence electrons: Electrons in the outermost shell; they determine an element's bonding behavior and reactivity.
Ionic bond: A bond formed by the transfer of electrons from a metal to a nonmetal, producing oppositely charged ions that attract.
Covalent bond: A bond formed when two nonmetal atoms share electrons.
Metallic bond: Bonding in metals where positive ions sit in a 'sea' of delocalized electrons, explaining conductivity and malleability.
Law of conservation of mass: Mass is neither created nor destroyed in a chemical reaction; the mass of reactants equals the mass of products.
Balanced equation: A chemical equation with equal numbers of each type of atom on both sides, satisfying conservation of mass.
Combustion reaction: A fuel reacts with oxygen to release energy, e.g. $\ce{CH4 + 2O2 -> CO2 + 2H2O}$ .
Synthesis reaction: Two or more reactants combine to form one product: $\ce{A + B -> AB}$ .
Decomposition reaction: One reactant breaks into two or more products: $\ce{AB -> A + B}$ .
Acid: A substance that donates H⁺ ions (or accepts electrons); has a pH below 7 and turns litmus red.
Base: A substance that accepts H⁺ (or donates OH⁻); has a pH above 7 and turns litmus blue.
pH scale: Measures acidity from 0–14; 7 is neutral, below 7 acidic, above 7 basic. Each unit is a tenfold change in H⁺ concentration.
States of matter: Solid (fixed shape/volume), liquid (fixed volume, takes shape of container), gas (fills container), plasma (ionized gas).
Phase changes: Melting, freezing, vaporization (boiling/evaporation), condensation, sublimation (solid→gas), deposition (gas→solid).
Endothermic vs. exothermic: Endothermic reactions absorb energy (surroundings cool); exothermic reactions release energy (surroundings warm).
Physical vs. chemical change: Physical change alters form but not identity (melting, cutting); chemical change forms new substances (burning, rusting).
Element, compound, mixture: Element = one kind of atom; compound = atoms chemically bonded in fixed ratio; mixture = physically combined, separable substances.
Solution: A homogeneous mixture of a solute dissolved in a solvent (e.g., salt water).
Density: Mass per unit volume: $\rho = \dfrac{m}{V}$ . An object floats if its density is less than the fluid's.
Newton's first law (inertia): An object at rest stays at rest, and an object in motion stays in motion at constant velocity, unless acted on by a net force.
Newton's second law: Net force equals mass times acceleration: $F = ma$ .
Newton's third law: For every action there is an equal and opposite reaction; forces come in pairs on different objects.
Speed vs. velocity: Speed is distance per time (scalar); velocity is speed with direction (vector).
Acceleration: The rate of change of velocity: $a = \dfrac{\Delta v}{\Delta t}$ . It occurs when speed or direction changes.
Kinetic energy: Energy of motion: $KE = \tfrac{1}{2}mv^2$ . It increases with the square of speed.
Potential energy (gravitational): Stored energy due to position: $PE = mgh$ .
Law of conservation of energy: Energy cannot be created or destroyed, only transformed from one form to another; total energy stays constant.
Work: Force applied over a distance in the direction of motion: $W = Fd$ . Measured in joules.
Power: The rate of doing work: $P = \dfrac{W}{t}$ . Measured in watts.
Momentum: The product of mass and velocity: $p = mv$ ; conserved in collisions in a closed system.
Friction: A force that opposes motion between surfaces in contact; converts kinetic energy to heat.
Gravity: An attractive force between masses; near Earth's surface it gives free-falling objects an acceleration of about $9.8\ \text{m/s}^2$ .
Mass vs. weight: Mass is the amount of matter (constant, kg); weight is the force of gravity on that mass ( $W = mg$ , varies by location).
Simple machines: Lever, pulley, wheel and axle, inclined plane, wedge, and screw; they change the size or direction of a force.
Mechanical advantage: How much a machine multiplies input force; it does not multiply work or energy (those are conserved).
Electromagnetic spectrum (order): Radio, microwave, infrared, visible light, ultraviolet, X-rays, gamma rays — increasing frequency and energy, decreasing wavelength.
Wave properties: Wavelength (crest-to-crest distance), frequency (waves per second), amplitude (height), and speed ( $v = f\lambda$ ).
Transverse vs. longitudinal waves: Transverse: medium moves perpendicular to wave travel (light); longitudinal: medium moves parallel (sound).
Reflection, refraction, diffraction: Reflection = bouncing off a surface; refraction = bending when entering a new medium; diffraction = spreading around obstacles.
Sound: A longitudinal mechanical wave that requires a medium; pitch depends on frequency and loudness on amplitude.
Ohm's law: Voltage equals current times resistance: $V = IR$ .
Series vs. parallel circuits: Series: one path, current is the same everywhere; parallel: multiple paths, voltage is the same across branches.
Conductor vs. insulator: Conductors (metals) let charge flow easily; insulators (rubber, glass) resist charge flow.
Electromagnet: A magnet created by current flowing through a coil of wire; its strength depends on current and number of coils.
Heat transfer methods: Conduction (direct contact), convection (fluid movement), and radiation (electromagnetic waves, no medium needed).
Temperature vs. heat: Temperature measures the average kinetic energy of particles; heat is the energy transferred between objects at different temperatures.
Nuclear fission vs. fusion: Fission splits a heavy nucleus releasing energy (nuclear plants); fusion joins light nuclei (powers the Sun), releasing even more energy.
Radioactive decay: Unstable nuclei emit alpha, beta, or gamma radiation, transforming into more stable elements over time.
Half-life: The time for half of a radioactive sample to decay; constant for a given isotope.
Energy forms: Mechanical, thermal, chemical, electrical, nuclear, electromagnetic, and sound — all interconvertible.
Net force: The vector sum of all forces on an object; zero net force means no acceleration (equilibrium).
Static electricity: Buildup of electric charge on a surface, often from friction; like charges repel and opposite charges attract.
Magnet poles: Every magnet has a north and south pole; like poles repel, opposite poles attract, and poles cannot be isolated.
Concentration (solution): The amount of solute per amount of solution; higher concentration means more dissolved solute.
Catalyst: A substance that speeds a reaction by lowering activation energy without being consumed.
Activation energy: The minimum energy needed to start a chemical reaction.
Molarity: Moles of solute per liter of solution; a common measure of concentration.
Boyle's law: At constant temperature, the pressure and volume of a gas are inversely related: $P_1 V_1 = P_2 V_2$ .
Charles's law: At constant pressure, a gas's volume is directly proportional to its absolute temperature.
Avogadro's number: $6.022 \times 10^{23}$ particles per mole; links the number of particles to the amount of substance.
Photosynthesis: Plants convert carbon dioxide and water into glucose and oxygen using light energy: $\ce{6CO2 + 6H2O -> C6H12O6 + 6O2}$ .
Where photosynthesis occurs: In the chloroplasts of plant cells, using the green pigment chlorophyll to capture light.
Cellular respiration: Cells break down glucose with oxygen to release energy (ATP): $\ce{C6H12O6 + 6O2 -> 6CO2 + 6H2O}$ .
Where respiration occurs: Mostly in the mitochondria of eukaryotic cells.
Photosynthesis vs. respiration: They are roughly reverse processes: photosynthesis stores energy in glucose; respiration releases it. Products of one are reactants of the other.
ATP: Adenosine triphosphate — the cell's main energy-carrying molecule, produced by respiration.
Anaerobic respiration (fermentation): Energy release without oxygen; in muscle it produces lactic acid, in yeast it produces alcohol and $\ce{CO2}$ .
Cell theory: All living things are made of cells, the cell is the basic unit of life, and all cells come from pre-existing cells.
Prokaryotic vs. eukaryotic: Prokaryotes (bacteria) lack a nucleus and membrane-bound organelles; eukaryotes (plants, animals) have both.
Nucleus: The organelle that contains the cell's DNA and controls cell activities.
Mitochondria: The 'powerhouse' organelle where most cellular respiration and ATP production occur.
Chloroplast: The organelle in plant cells where photosynthesis takes place; contains chlorophyll.
Cell membrane: The selectively permeable boundary controlling what enters and leaves the cell.
Cell wall: A rigid outer layer in plant, fungal, and bacterial cells that provides support and protection; absent in animal cells.
Ribosome: The site of protein synthesis (translation) in the cell.
Diffusion: Movement of particles from high to low concentration; passive, requiring no energy.
Osmosis: Diffusion of water across a selectively permeable membrane from low to high solute concentration.
Active transport: Movement of substances against a concentration gradient, requiring energy (ATP).
DNA: Deoxyribonucleic acid — a double helix of nucleotides (A-T, G-C base pairs) that stores genetic information.
Gene: A segment of DNA that codes for a protein or trait.
Chromosome: A condensed structure of DNA and protein; humans have 23 pairs (46 total).
Mitosis: Cell division producing two genetically identical diploid cells, used for growth and repair.
Meiosis: Cell division producing four genetically varied haploid gametes (sex cells) with half the chromosome number.
Dominant vs. recessive allele: A dominant allele is expressed when present; a recessive allele is masked unless two copies are inherited.
Genotype vs. phenotype: Genotype is the genetic makeup (e.g., Bb); phenotype is the observable trait (e.g., brown eyes).
Homozygous vs. heterozygous: Homozygous = two identical alleles (BB or bb); heterozygous = two different alleles (Bb).
Punnett square: A diagram predicting offspring genotype and phenotype ratios from the parents' alleles.
DNA replication: The semiconservative copying of DNA before cell division; each new molecule keeps one original strand.
Transcription and translation: Transcription copies DNA into mRNA; translation uses mRNA at the ribosome to build a protein.
Mutation: A change in DNA sequence; it can be harmful, beneficial, or neutral and is the ultimate source of genetic variation.
Natural selection: Individuals with traits better suited to the environment survive and reproduce more, passing those traits on.
Evolution: Change in the inherited traits of a population over generations; descent with modification.
Adaptation: An inherited trait that improves an organism's survival or reproduction in its environment.
Evidence for evolution: Fossils, homologous structures, embryology, DNA/molecular similarities, and observed natural selection.
Species: A group of organisms that can interbreed and produce fertile offspring.
Taxonomy (Linnaean order): Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species — broadest to most specific.
Producer: An autotroph that makes its own food via photosynthesis (or chemosynthesis); the base of a food chain.
Consumer: A heterotroph that eats other organisms; classified as herbivore, carnivore, or omnivore.
Decomposer: An organism (bacteria, fungi) that breaks down dead matter and recycles nutrients into the ecosystem.
Food web: Interconnected food chains showing energy flow through an ecosystem from producers up to top consumers.
10% rule (energy transfer): Only about 10% of energy passes from one trophic level to the next; the rest is lost as heat.
Carbon cycle: Carbon moves among the atmosphere, organisms, oceans, and rocks via photosynthesis, respiration, decay, and combustion.
Nitrogen cycle: Bacteria convert atmospheric nitrogen into usable forms (fixation) that organisms use to build proteins and DNA.
Water cycle: Evaporation, condensation, precipitation, and collection circulate water through the environment.
Carrying capacity: The maximum population size an environment can sustain given its resources.
Limiting factor: A resource or condition (food, water, space, predators) that limits a population's growth.
Biome: A large region defined by its climate and characteristic plants and animals (e.g., desert, tundra, rainforest).
Ecosystem: A community of living organisms interacting with their nonliving (abiotic) environment.
Symbiosis types: Mutualism (both benefit), commensalism (one benefits, other unaffected), parasitism (one benefits, host harmed).
Predator-prey relationship: Predator and prey populations cycle: prey rises, predators rise, prey falls, predators fall.
Homeostasis: The maintenance of stable internal conditions (temperature, pH, water) despite a changing environment.
Enzyme: A protein catalyst that speeds biological reactions; specific to its substrate and sensitive to temperature and pH.
Circulatory system: The heart, blood, and vessels that transport oxygen, nutrients, and wastes throughout the body.
Respiratory system: Lungs and airways that exchange oxygen and carbon dioxide between the body and the air.
Digestive system: Organs that break down food into nutrients the body can absorb and use.
Nervous system: The brain, spinal cord, and nerves that sense stimuli and coordinate responses.
Macromolecules of life: Carbohydrates (energy), lipids (storage/membranes), proteins (structure/enzymes), and nucleic acids (genetic info).
Asexual vs. sexual reproduction: Asexual produces genetically identical offspring from one parent; sexual combines two parents' genes, increasing variation.
Biodiversity: The variety of life in an ecosystem; greater biodiversity generally makes an ecosystem more stable and resilient.
Ecological succession: The gradual change in a community over time — primary (bare rock) or secondary (after a disturbance like fire).
Earth's layers (outer to inner): Crust, mantle, outer core (liquid), inner core (solid).
Mantle: The thick layer beneath the crust that behaves as a slowly flowing solid; convection currents here drive plate movement.
Outer vs. inner core: The outer core is liquid (molten iron and nickel) and generates Earth's magnetic field; the inner core is solid due to immense pressure.
Plate tectonics: The theory that Earth's rigid outer shell is broken into plates that slowly move over the softer mantle below.
Divergent boundary: Plates pull apart; magma rises to form new crust, creating mid-ocean ridges and rift valleys.
Convergent boundary: Plates collide; the denser plate subducts, forming volcanoes, mountains, and deep ocean trenches.
Transform boundary: Plates slide past each other horizontally, producing earthquakes (e.g., the San Andreas Fault).
Driver of plate motion: Convection currents in the mantle, powered by Earth's internal heat, move the plates.
Continental drift (Pangaea): Wegener's hypothesis that continents were once joined in a single landmass (Pangaea) and have since drifted apart.
Earthquakes and volcanoes location: Concentrated along plate boundaries, especially the Pacific 'Ring of Fire.'
Igneous rock: Forms from the cooling and solidifying of molten magma or lava (e.g., granite, basalt).
Sedimentary rock: Forms when sediments are compacted and cemented over time (e.g., sandstone, limestone); may contain fossils.
Metamorphic rock: Forms when existing rock is changed by heat and pressure (e.g., marble from limestone).
Rock cycle: The continuous transformation among igneous, sedimentary, and metamorphic rock through melting, weathering, and pressure.
Weathering vs. erosion: Weathering breaks rock down in place (physical or chemical); erosion transports the pieces away by wind, water, or ice.
Mineral: A naturally occurring, inorganic solid with a definite chemical composition and crystal structure.
Fossil: Preserved remains or traces of past life, most often found in sedimentary rock.
Law of superposition: In undisturbed rock layers, the oldest layers are at the bottom and the youngest at the top.
Relative vs. absolute dating: Relative dating orders events (older/younger); absolute dating gives a numeric age, often via radioactive decay.
Layers of the atmosphere: Troposphere, stratosphere (ozone), mesosphere, thermosphere, exosphere — from the surface upward.
Ozone layer: A region in the stratosphere that absorbs most of the Sun's harmful ultraviolet radiation.
Greenhouse effect: Atmospheric gases (CO₂, water vapor, methane) trap heat, warming Earth's surface; excess gas intensifies warming.
Water cycle (Earth): Evaporation, transpiration, condensation, precipitation, and runoff continually move water through Earth's systems.
Weather vs. climate: Weather is short-term atmospheric conditions; climate is the long-term average weather of a region.
Air masses and fronts: A front is the boundary between air masses; cold fronts often bring storms, warm fronts bring gradual precipitation.
Ocean currents: Large-scale movements of seawater driven by wind, temperature, and salinity that redistribute heat around the globe.
Tides: The regular rise and fall of sea level caused mainly by the Moon's gravitational pull, with the Sun contributing.
Solar system order: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune — inner rocky planets, then outer gas/ice giants.
Earth's rotation vs. revolution: Rotation (spin on its axis, ~24 h) causes day and night; revolution (orbit around the Sun, ~365 days) defines a year.
Cause of seasons: The tilt of Earth's axis (about 23.5°), not its distance from the Sun, causes the seasons.
Moon phases: New, waxing crescent, first quarter, waxing gibbous, full, waning gibbous, third quarter, waning crescent — driven by Sun-Earth-Moon geometry.
Solar vs. lunar eclipse: Solar: Moon passes between Sun and Earth, blocking the Sun. Lunar: Earth passes between Sun and Moon, casting a shadow on the Moon.
Star life cycle: Stars form from gas/dust nebulae, fuse hydrogen as main-sequence stars, then expand and end as white dwarfs, neutron stars, or black holes.
The Sun: A medium-sized star that produces energy by nuclear fusion of hydrogen into helium; the source of Earth's energy.
Galaxy: A vast system of stars, gas, and dust bound by gravity; our solar system lies in the Milky Way galaxy.
Big Bang theory: The leading explanation that the universe began ~13.8 billion years ago from an extremely hot, dense state and has been expanding since.
Gravity in space: Gravity holds planets in orbit around the Sun and moons around planets; orbital paths are ellipses.
Renewable vs. nonrenewable resources: Renewable resources (solar, wind, hydro) replenish naturally; nonrenewable (coal, oil, gas) form over millions of years.
Topographic map: A map using contour lines to show elevation; closely spaced lines indicate steep terrain.
Comet, asteroid, meteor: Comets are icy bodies with tails; asteroids are rocky bodies (mostly between Mars and Jupiter); a meteor is debris burning up in the atmosphere.

To find us again, just search “Career Employer Praxis General Science (5435)”

By Career EmployerUpdated Sep 12, 2026

200+ free Praxis 5435 flashcards — 4 ways to study

Praxis 5435 Flashcard of the DayNew daily

The classic card. Do you know this one?

Click Study Flashcards above to open the flashcard hub — 200 Praxis 5435 cards you can flip, match, type, or quiz yourself on. Every card is drawn from the ETS content categories, so you study exactly what the test measures.^[1] Pair them with our free practice test and study guide.

Praxis 5435 is one of the 7 Praxis exams — explore our Praxis flashcards to compare and prep across the whole family.

Praxis 5435 Flashcard Study Modes

Flip mode lets you move through each card front and back at your own pace. Match times you as you pair terms with definitions. Type shows the definition and asks you to produce the term, so something like Osmosis has to come from memory rather than recognition. Quiz builds multiple choice questions from the same cards, so you practice choosing between options that look close.

Free Praxis 5435 flashcards from Career Employer — active recall for the ETS General Science exam

Why Flashcards Work for the Praxis 5435

Physical Science is the largest block in the deck at 70 cards, and it drills the chemistry and physics vocabulary that runs through most of the test. On the chemistry side you get compact definitions behind terms such as Ion, Acid, and Base; on the physics side the cards push quantities and phenomena like Work, Power, and Density. Sound and Gravity sit here too, so treat this domain as precise vocabulary before you treat it as calculation.

Life Science follows with 60 cards covering molecules, cells, and systems. Expect the core abbreviations on cards like ATP and DNA, cell structures and processes behind Nucleus, Mitosis, and Enzyme, and the wider view of living systems in fronts such as Gene and Biome. Osmosis is the kind of card that rewards a definition you can say in one clean sentence rather than a vague sense of what happens.

Earth and Space Science brings 40 cards spanning the planet and what surrounds it. Terrestrial fronts include Mantle, Mineral, and Rock cycle, while Fossil ties the rock record to change over time. Sky and system cards run from Tides through The Sun to Galaxy, and Ozone layer connects atmosphere to the questions about human impact you will meet elsewhere in the deck.

Nature and Impact of Science and Engineering rounds things out with 30 cards on how science is actually done and judged. You get inquiry vocabulary in Hypothesis, Falsifiable, and Control group, quality checks in Peer review and Replication, and measurement and error language in SI base units and Random error. Pseudoscience is here as the contrast case, which makes these cards useful for the reasoning items rather than the content recall items.

The Praxis 5435 rewards instant recall of science facts, formulas, and vocabulary across four subjects.^[1] Spaced flashcards are the most efficient way to make that knowledge automatic — especially for the science areas you studied least in school. Used alongside our practice test and study guide, they turn review time into measurable progress.

Praxis 5435 Flashcards by Category

The cards are organized by the 5435’s four content categories. Drill the highest-weighted one first — Physical Science is roughly a third of the test — then Life Science and Earth and Space Science:^[1]

Praxis 5435 flashcards by content category
Content category	What it covers
Nature & Impact of Science & Engineering	Scientific method, measurement, accuracy vs. precision, engineering design
Physical Science	Atoms, periodic table, bonding, reactions, forces, energy, waves, electricity
Life Science	Cells, photosynthesis & respiration, genetics, evolution, ecology
Earth & Space Science	Earth's structure, plate tectonics, rocks, atmosphere, weather, astronomy

How to Get the Most Out of These Flashcards

Start with Physical Science. At 70 cards it is the biggest domain in the deck, and its vocabulary supports questions you will meet again in the other three domains.
Type-drill the confusable pairs. Acid and Base belong together, and so do Work and Power, because Type forces the exact term instead of letting you settle for a near match.
Use Match for the process cards. Timed pairing works well on Life Science fronts like Mitosis and Enzyme, where the definitions look similar until you have seen them a few times.
Move to the practice test once recall holds. When Quiz scores stay steady across Earth and Space Science and Nature and Impact of Science and Engineering, switch over to test the same terms in question form.
Keep the cadence small. Work one domain per session across the 200 cards, re-Flip yesterday’s misses before starting new material, and come back to the study guide for anything a card definition leaves thin.

Praxis 5435 Flashcards FAQ

Two hundred free Praxis General Science (5435) flashcards, organized across all four content categories — Nature and Impact of Science and Engineering, Physical Science, Life Science, and Earth and Space Science. They're free with no account required.

References

1.ETS. “Praxis General Science: Content Knowledge (5435) — Test Overview.” ETS. ↑
2.NASA Science. “Introduction to the Electromagnetic Spectrum.” NASA. ↑
3.U.S. Geological Survey. “Understanding Plate Motions.” USGS. ↑

Career Employer

Career Employer is the ultimate resource to help you get started working the job of your dreams. We cover topics from general career information, career searching, exam preparation with free study materials, career interviewing, and becoming successful in your career of choice.

All Posts

Career Employer’s Editorial Process

Here at Career Employer, we focus a lot on providing factually accurate information that is always up to date. We strive to provide correct information using strict editorial processes, article editing, and fact-checking for all of the information found on our website. We only utilize trustworthy and relevant resources. To find out more, make sure to read our full editorial process page here.