Science Quiz Questions & Answers 2026 — 100 Q&A

Why Science Knowledge Matters

Science literacy is essential in the modern world. Understanding basic scientific principles helps you make informed decisions about health, technology, and the environment. Science quiz questions test your grasp of how the natural world works.

Physics — Key Facts for Quiz Success

• ⚡ Speed of light: 299,792,458 metres per second
• 🍎 Newton's First Law: Objects remain at rest or in uniform motion unless acted upon by a force.
• 🔋 E = mc² means energy equals mass times the speed of light squared.
• 🧲 Opposite magnetic poles attract; like poles repel.
• 🌡️ Absolute zero is −273.15°C (0 Kelvin) — the coldest possible temperature.
• 🔊 Sound travels at approximately 343 m/s in air at room temperature.

Chemistry — Essential Quiz Knowledge

• 💧 Water's chemical formula is H₂O — two hydrogen atoms bonded to one oxygen.
• 🧪 The most abundant element in the universe is Hydrogen.
• ⚗️ The most abundant element in Earth's crust is Oxygen (46%).
• 🔥 Combustion requires three elements: fuel, oxygen, and heat (the "fire triangle").
• 💎 Diamond is the hardest natural substance (10 on Mohs scale); graphite is the softest form of carbon.
• 🧂 Common table salt is Sodium Chloride (NaCl).

Biology — Must-Know Facts

• 🦠 The human body contains approximately 37.2 trillion cells.
• 🧬 DNA stands for Deoxyribonucleic Acid — the molecule that carries genetic information.
• ❤️ The human heart beats approximately 100,000 times per day.
• 🫁 The largest organ is the skin — the liver is the largest internal organ.
• 🐛 Insects are the most numerous animals on Earth, comprising over 80% of all animal species.
• 🌿 Photosynthesis produces oxygen and glucose using sunlight, water, and CO₂.

Astronomy — Space Science Quiz Questions

• 🌍 Earth is the third planet from the Sun, approximately 150 million km away.
• ☀️ The Sun is a G-type main-sequence star — one of 200–400 billion stars in the Milky Way.
• 🪐 Saturn's rings are made of ice and rock particles, some as small as grains of sand.
• 🌑 A light-year is the distance light travels in one year: approximately 9.46 trillion km.
• 🔭 The Hubble Space Telescope was launched in 1990.
• 🚀 The first human in space was Yuri Gagarin in April 1961.

50 Science Quiz Questions Answered

Physics

1. What force keeps planets in orbit around the Sun? (Gravity)
2. What type of energy does a moving object have? (Kinetic energy)
3. What is the unit of electrical resistance? (Ohm)
4. What phenomenon explains why the sky is blue? (Rayleigh scattering)
5. What is the boiling point of water in Fahrenheit? (212°F)

Chemistry

1. What is the atomic number of carbon? (6)
2. Which gas is used in party balloons? (Helium)
3. What is the pH of pure water? (7 — neutral)
4. What metal is liquid at room temperature? (Mercury)
5. What is dry ice made of? (Solid carbon dioxide)

Biology

1. How many chambers does the human heart have? (4)
2. What organ produces insulin? (Pancreas)
3. What is the basic unit of life? (Cell)
4. How many bones are in the adult human body? (206)
5. What type of blood cells carry oxygen? (Red blood cells / Erythrocytes)

Tips to Ace Science Quizzes

1. Learn the periodic table basics — at least the first 20 elements.
2. Understand key formulas — F=ma, E=mc², PV=nRT.
3. Watch science YouTube channels — Kurzgesagt, MinutePhysics, Veritasium.
4. Practice with timed quizzes — speed matters in competitive settings.
5. Connect concepts — understanding WHY is more memorable than memorizing facts.