Whether you’re a student, trivia lover, or science nerd, these chemistry quiz questions will test your knowledge of the periodic table, bonding, reactions, and everyday chemistry facts. Each round includes 10 thoughtfully crafted questions—some with surprising explanations to boost your learning while you play.
Round 1: General Chemistry Basics
What is the chemical symbol for gold?
Answer: Au It comes from the Latin word aurum, meaning “shining dawn.”
What is H₂O more commonly known as?
Answer: Water Two hydrogen atoms and one oxygen atom form this essential molecule.
Which gas do humans need to breathe for survival?
Answer: Oxygen O₂ is essential for cellular respiration.
What is the pH of a neutral solution at 25°C?
Answer: 7 The pH scale runs from 0 (acidic) to 14 (basic), and 7 is neutral.
What state of matter has a definite volume but no definite shape?
Answer: Liquid Liquids flow to fill the shape of their container while retaining volume.
What element has the atomic number 1?
Answer: Hydrogen It’s the lightest and most abundant element in the universe.
Which scientist created the periodic table?
Answer: Dmitri Mendeleev He arranged elements by atomic mass, leading to the modern table.
What does NaCl stand for?
Answer: Sodium chloride Also known as table salt.
Which branch of chemistry studies carbon-containing compounds?
Answer: Organic chemistry It includes compounds with carbon-hydrogen bonds.
What type of bond involves the sharing of electrons?
Answer: Covalent bond This type of bond is common in molecules like water and methane.
Round 2: Atoms, Elements & the Periodic Table
Which element is a noble gas?
Answer: Neon Noble gases like helium and argon are inert and found in Group 18.
What is the lightest noble gas?
Answer: Helium It’s non-reactive and used in balloons because it’s lighter than air.
How many protons does carbon have?
Answer: 6 The atomic number of carbon is 6, which equals its number of protons.
What is the most abundant element in Earth’s crust?
Answer: Oxygen It makes up about 46% of the crust by weight.
Which metal is liquid at room temperature?
Answer: Mercury It’s toxic and used in old thermometers.
Which element is needed for healthy thyroid function?
Answer: Iodine It’s added to table salt to prevent deficiencies.
What is the only letter not found in any chemical symbol?
Answer: J No element uses the letter “J” in its symbol.
What do you call atoms of the same element with different numbers of neutrons?
Answer: Isotopes They have the same atomic number but different mass numbers.
What is the symbol for potassium?
Answer: K It comes from the Latin word kalium.
Which group of elements is the most reactive with water?
Answer: Alkali metals Group 1 metals like sodium and potassium react violently with water.
Round 3: Chemical Reactions & Lab Knowledge
What is the name of the reaction between an acid and a base?
Answer: Neutralization It forms water and a salt.
What gas is produced when vinegar reacts with baking soda?
Answer: Carbon dioxide This reaction causes foaming in many school science experiments.
Which part of the Bunsen burner is adjusted to control air flow?
Answer: The collar Turning the collar changes the flame from yellow (cooler) to blue (hotter).
What is the energy needed to start a reaction called?
Answer: Activation energy It’s the initial energy input needed to break bonds.
What do we call a substance that speeds up a reaction but is not consumed?
Answer: Catalyst Enzymes are biological examples of catalysts.
What color does litmus paper turn in acid?
Answer: Red Blue litmus paper turns red in acidic solutions.
What is the chemical formula for methane?
Answer: CH₄ It’s the simplest hydrocarbon and a potent greenhouse gas.
Which law states that mass is conserved in a chemical reaction?
Answer: Law of Conservation of Mass No atoms are lost or gained; they are simply rearranged.
What is formed when a metal reacts with an acid?
Answer: A salt and hydrogen gas For example, zinc + hydrochloric acid → zinc chloride + hydrogen.
Which piece of lab equipment is used to measure exact liquid volumes?
Answer: Burette Used in titrations for precise delivery of liquids.
Round 4: Real-World Chemistry & Applications
Which vitamin is also known as ascorbic acid?
Answer: Vitamin C It’s essential for immune function and collagen production.
What gas makes drinks fizzy?
Answer: Carbon dioxide CO₂ is dissolved under pressure to create carbonation.
What element gives fireworks a red colour?
Answer: Strontium Different metal salts produce different flame colours.
Which chemical is most commonly used for disinfecting water?
Answer: Chlorine It kills bacteria and pathogens in public water systems.
Which greenhouse gas is released during combustion of fossil fuels?
Answer: Carbon dioxide CO₂ traps heat in the atmosphere and contributes to global warming.
What’s the main ingredient in glass?
Answer: Silica (sand) Glass is made by heating silica with other compounds like soda ash.
What acid is found in your stomach?
Answer: Hydrochloric acid (HCl) It helps digest food and kills harmful microbes.
What metal is used in thermometers and must be handled with care?
Answer: Mercury Due to its toxicity, it’s being phased out of most devices.
Which household item contains acetic acid?
Answer: Vinegar Acetic acid gives vinegar its sharp smell and taste.
Which gas is essential for combustion to occur?
Answer: Oxygen Without oxygen, fire cannot be sustained.
Round 5: Advanced & Bonus Chemistry
Which element is used in most nuclear reactors as fuel?
Answer: Uranium Specifically, uranium-235 is used in fission reactions.
What type of chemical reaction absorbs heat?
Answer: Endothermic Examples include photosynthesis and thermal decomposition.
Which scientist developed the planetary model of the atom?
Answer: Niels Bohr He proposed electrons orbit the nucleus in defined shells.
What’s the name of the negatively charged subatomic particle?
Answer: Electron It orbits the nucleus and determines chemical reactivity.
Which law describes the relationship between pressure and volume of a gas?
Answer: Boyle’s Law It states that pressure is inversely proportional to volume (P ∝ 1/V).
Which acid is used in car batteries?
Answer: Sulfuric acid It reacts with lead plates to generate electricity.
What’s the term for a solution that resists pH change?
Answer: Buffer Buffers stabilize pH in biological and chemical systems.
Which polymer is used to make plastic bottles?
Answer: PET (Polyethylene terephthalate) It’s lightweight, recyclable, and commonly found in packaging.
What is the main component of natural gas?
Answer: Methane CH₄ is a simple hydrocarbon used widely as fuel.
Conclusion
You’ve just completed 50 in-depth chemistry quiz questions—from atoms and acids to everyday materials and scientific laws. Whether you breezed through or learned something new along the way, this chemistry quiz is a powerful way to sharpen your scientific thinking.
Want to go deeper? Bookmark this page or share it with your fellow quiz lovers—there’s always more to explore in the world of chemistry. And remember: the best way to remember science is to stay curious and keep testing yourself with chemistry quiz questions like these.
