Science Quiz Questions and Answers

Science questions across the main disciplines: the periodic table and chemical symbols, forces and motion, human biology, and the solar system. They start with the fundamentals and build towards questions that need real subject knowledge.

180 questions · four difficulty tiers · free to play, no sign-up

Easy Medium Hard Legends

Play the Science quiz 180 questions · climb four tiers · free, no sign-up

Easy questions 45

What is the chemical symbol for oxygen? O
Which sense organ do we use to smell? Nose
Which force pulls objects towards the Earth? Gravity
Which organ pumps blood around the body? Heart
What do bees collect from flowers to make honey? Nectar
What gas do humans need to breathe in to survive? Oxygen
How many legs does an insect have? Six
What is the closest star to Earth? The Sun
H2O is commonly known as what? Water
Which planet is known as the Red Planet? Mars
Which organ pumps blood around the human body? The heart
Plants make their food from sunlight in a process called…? Photosynthesis
How many bones are in the adult human body? 206
What is the largest planet in our solar system? Jupiter
Which gas do plants absorb from the air? Carbon dioxide
Which part of the body do we use for hearing? The ears
Water is made of hydrogen and which other element? Oxygen
What force pulls objects towards the Earth? Gravity
How many lungs does a human have? Two
What is frozen water called? Ice
Which is the largest animal on Earth? The blue whale
The Sun is mostly made of which gas? Hydrogen
What do we call animals that eat only plants? Herbivores
What is the centre of an atom called? The nucleus
Which planet do we live on? Earth
What is the boiling point of water in Celsius at sea level? 100
What do bees collect from flowers? Nectar
Which sense do we use our nose for? Smell
What is the green pigment in plants called? Chlorophyll
How many planets are in our solar system? Eight
What state of matter is steam? Gas
What do we call animals that are active at night? Nocturnal
Which body part controls your thoughts and movements? The brain
What is the fastest land animal? The cheetah
Which planet is closest to the Sun? Mercury
What do caterpillars turn into? Butterflies
Which gas makes up most of the air we breathe? Nitrogen
What is the hardest natural substance? Diamond
How many teeth does a typical adult human have? 32
What do we call water falling from clouds? Rain
Which blood cells help fight infection? White blood cells
What is the study of living things called? Biology
Which instrument is used to see tiny things like cells? A microscope
What is Earth's only natural satellite? The Moon
Which season typically follows winter? Spring

Medium questions 45

What is the boiling point of water in degrees Celsius? 100
Which gas do plants absorb for photosynthesis? Carbon dioxide
What is the largest organ of the human body? Skin
Which organelle is called the powerhouse of the cell? Mitochondria
The speed of light is about how many km per second? 300,000
What is the chemical symbol for gold? Au
Which gas do plants release during photosynthesis? Oxygen
What is often called the powerhouse of the cell? The mitochondria
How many chromosomes do humans normally have? 46
What is the chemical symbol for sodium? Na
Which planet has the most prominent ring system? Saturn
The Sun gives Earth energy mainly as light and…? Heat
What is the most abundant gas in Earth's atmosphere? Nitrogen
What is the basic unit of life? The cell
Who proposed evolution by natural selection? Charles Darwin
What is the chemical formula for table salt? NaCl
What force resists motion between two surfaces in contact? Friction
Roughly how many bones is a human baby born with? About 300
What is the largest organ in the human body? The skin
Which planet is famous for a giant red spot? Jupiter
What is the SI unit of electric current? The ampere
Which part of a plant carries out most photosynthesis? The leaves
Which gas do humans breathe out? Carbon dioxide
Which metal is liquid at room temperature? Mercury
The speed of light is approximately how fast? 300,000 km/s
Which vitamin does skin produce in sunlight? Vitamin D
What is the chemical symbol for iron? Fe
What is the process of a liquid turning into a gas called? Evaporation
How many planets in our solar system have ring systems? Four
What is the smallest unit of an element that keeps its properties? The atom
Which blood type is known as the universal donor? O negative
What do we call a push or pull on an object? A force
Which planet rotates on its side? Uranus
What is the hardest substance produced by the human body? Tooth enamel
What is the study of weather called? Meteorology
What is the chemical symbol for potassium? K
Which scientist is famous for the theory of gravity and a falling apple? Isaac Newton
Which gas is the main human-made driver of the greenhouse effect? Carbon dioxide
What do we call animals without a backbone? Invertebrates
How long does Earth take to orbit the Sun once? One year
What is the chemical symbol for carbon? C
Which organ filters blood and produces urine? The kidneys
What is the most abundant element in the universe? Hydrogen
Sound travels fastest through which medium? A solid
What do we call animals that eat both plants and meat? Omnivores

Hard questions 45

Which scientist is famous for the laws of planetary motion? Johannes Kepler
What type of energy is stored in a stretched spring? Potential
Which blood cells mainly fight infection? White blood cells
What is the pH of a neutral solution? 7
Who proposed the theory of general relativity? Albert Einstein
What is the second most abundant element in the universe? Helium
What is the SI unit of force? The newton
What is the pH of pure, neutral water? 7
Which subatomic particle carries a negative charge? The electron
What is the chemical symbol for silver? Ag
Which scientist developed the theory of general relativity? Albert Einstein
What is the type of cell division that produces sex cells (gametes)? Meiosis
What is the largest moon in our solar system? Ganymede
What is the SI unit of frequency? The hertz
Which gas makes up about 21% of Earth's atmosphere? Oxygen
What is the chemical symbol for lead? Pb
Which part of the cell contains the DNA? The nucleus
What does DNA stand for? Deoxyribonucleic acid
The speed of sound in air is approximately how many metres per second? 343
Which scientist is known for the laws of planetary motion? Johannes Kepler
What is the most abundant metal in the Earth's crust? Aluminium
What is a substance that speeds up a reaction without being used up? A catalyst
Which blood vessels carry blood away from the heart? Arteries
How many chambers does the human heart have? Four
What is the chemical symbol for tin? Sn
What is the process of plants losing water vapour through their leaves? Transpiration
Which planet has a day longer than its year? Venus
What is the SI unit of energy? The joule
What type of chemical bond involves sharing electrons? A covalent bond
Who is credited with discovering penicillin? Alexander Fleming
What is the largest artery in the human body? The aorta
What is the chemical symbol for helium? He
What is the boiling point of water in Fahrenheit at sea level? 212
Which gas is responsible for the smell of rotten eggs? Hydrogen sulfide
What is the term for animals that keep a constant body temperature? Warm-blooded
What is the study of fungi called? Mycology
Which scientist created the periodic table of elements? Dmitri Mendeleev
What is the SI unit of electrical resistance? The ohm
Which is the hottest planet in our solar system? Venus
What is the chemical symbol for calcium? Ca
What is the change of state from a gas directly to a solid called? Deposition
How many pairs of chromosomes do humans have? 23
Which is the least dense (lightest) metal on the periodic table? Lithium
What is the energy stored due to an object's position called? Potential energy
What is the chemistry unit for the amount of a substance? The mole

Legends questions 45

What is the chemical symbol for nitrogen? N
Who formulated the three laws of motion? Isaac Newton
What is the change of a liquid to a gas below its boiling point called? Evaporation
What is the SI unit of power? Watt
Which law of thermodynamics states energy cannot be created or destroyed? First
What is the SI unit of electric charge? The coulomb
Which particle, found at CERN in 2012, completed the Standard Model? The Higgs boson
What is Avogadro's number, approximately (particles per mole)? 6.02 x 10^23
Which law states a gas's pressure and volume are inversely related at constant temperature? Boyle's law
Which element is the most electronegative? Fluorine
Which physicist formulated the uncertainty principle? Werner Heisenberg
What is the smallest particle (quantum) of light called? The photon
Which protein carries oxygen in red blood cells? Haemoglobin
The concept of 'half-life' is used to measure what? Radioactive decay
The second law of thermodynamics describes the tendency towards…? Entropy
Which scientist discovered the elements polonium and radium? Marie Curie
What is the chemical symbol for tungsten? W
What is absolute zero, approximately, in Celsius? -273 degrees
Which gas law relates volume and temperature at constant pressure? Charles's law
Which type of electromagnetic radiation has the highest energy? Gamma rays
Who proposed the atomic model with electrons in fixed orbital shells? Niels Bohr
What is the term for regrowing lost body parts, as a starfish does? Regeneration
Which is the strongest of the four fundamental forces? The strong nuclear force
Who modelled DNA's double-helix structure together with Francis Crick? James Watson
What is the SI unit of inductance? The henry
What is the most abundant element in the Earth's crust by mass? Oxygen
What is the process of splitting an atomic nucleus to release energy? Nuclear fission
What process powers the Sun, fusing hydrogen into helium? Nuclear fusion
Quarks are the building blocks of which particles? Protons and neutrons
What is the SI unit of magnetic flux density? The tesla
What is the boundary around a black hole, beyond which nothing escapes? The event horizon
Which element has the atomic number 6? Carbon
A solution with a pH greater than 7 is described as…? Alkaline
Which fundamental particle has no electric charge and barely interacts with matter? The neutrino
What is the change of state from a solid directly to a gas? Sublimation
Which organelle is responsible for protein synthesis in a cell? The ribosome
What is the SI unit of pressure? The pascal
Which scientist is famous for the equation E = mc squared? Albert Einstein
Which is the densest naturally occurring element? Osmium
What is the term for the genetic makeup of an organism? Genotype
What type of chemical reaction releases heat to its surroundings? Exothermic
What is the approximate age of the universe? About 13.8 billion years
Which law states that force equals mass times acceleration? Newton's second law
What is the term for organisms that make their own food, like plants? Autotrophs
Which scientist discovered the electron? J.J. Thomson

More quizzes

Wrestling quiz answers Leeds Rhinos quiz answers Manchester United quiz answers Arsenal quiz answers Premier League quiz answers The Bible quiz answers Sport quiz answers Music quiz answers History quiz answers Film & TV quiz answers

Play the Science quiz Test yourself properly · four tiers · free