Periodic Table & Elements MCQs 2026
101 questions with detailed answers · 0 from past papers · 11 quiz batches available
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- Q1medium
Elements in the periodic table are arranged primarily according to which property
💡 Explanation:The modern periodic table arranges elements in order of increasing atomic number.
- Q2easy
What is the chemical symbol for Potassium
💡 Explanation:Potassium's chemical symbol K comes from its Latin name "Kalium."
- Q3easy
Which chemical element, symbol Cl, is commonly used to disinfect drinking water and swimming pools
💡 Explanation:Chlorine, symbol Cl, is widely used as a disinfectant for water treatment and swimming pools.
- Q4easy
Which gas is commonly used to fill balloons for buoyancy due to its low density and non-flammability
💡 Explanation:Helium is commonly used to fill balloons due to its low density and non-flammable nature, unlike hydrogen.
- Q5easy
What is the chemical symbol for Gold
💡 Explanation:Gold's chemical symbol Au comes from its Latin name "Aurum."
- Q6easy
What is the chemical symbol for Silver
💡 Explanation:Silver's chemical symbol Ag comes from its Latin name "Argentum."
- Q7easy
What is the chemical symbol for Iron
💡 Explanation:Iron's chemical symbol Fe comes from its Latin name "Ferrum."
- Q8easy
What is the chemical symbol for Sodium
💡 Explanation:Sodium's chemical symbol Na comes from its Latin name "Natrium."
- Q9medium
What term describes elements arranged in vertical columns of the periodic table
💡 Explanation:Vertical columns in the periodic table are called groups (or families).
- Q10medium
What term describes elements arranged in horizontal rows of the periodic table
💡 Explanation:Horizontal rows in the periodic table are called periods.
- Q11medium
Which group of elements is known as the "Alkaline Earth Metals," including calcium and magnesium
💡 Explanation:Group 2 elements are known as the Alkaline Earth Metals, including calcium and magnesium.
- Q12medium
Which group of elements in the periodic table is known as the "Halogens," including chlorine and iodine
💡 Explanation:Group 17 elements are known as the Halogens, including fluorine, chlorine, bromine, and iodine.
- Q13medium
Which group of elements in the periodic table is known as the "Alkali Metals," including sodium and potassium
💡 Explanation:Group 1 elements, excluding hydrogen, are known as the Alkali Metals, including sodium and potassium.
- Q14medium
Which group of elements in the periodic table is known as the "Noble Gases," characterized by low reactivity
💡 Explanation:Group 18 elements are known as the Noble Gases, characterized by their general lack of reactivity.
- Q15easy
What is the chemical symbol for Lead
💡 Explanation:Lead's chemical symbol Pb comes from its Latin name "Plumbum."
- Q16medium
What is the chemical symbol for Tin
💡 Explanation:Tin's chemical symbol Sn comes from its Latin name "Stannum."
- Q17easy
What is the chemical symbol for Copper
💡 Explanation:Copper's chemical symbol Cu comes from its Latin name "Cuprum."
- Q18medium
What is the chemical symbol for Mercury
💡 Explanation:Mercury's chemical symbol Hg comes from its Latin/Greek name "Hydrargyrum," meaning liquid silver.
- Q19medium
What is the chemical symbol for Tungsten
💡 Explanation:Tungsten's chemical symbol W comes from its German name "Wolfram."
- Q20easy
What is the atomic number of Hydrogen
💡 Explanation:Hydrogen has an atomic number of 1, the simplest and lightest element.
- Q21easy
What is the atomic number of Oxygen
💡 Explanation:Oxygen has an atomic number of 8.
- Q22easy
What is the atomic number of Carbon
💡 Explanation:Carbon has an atomic number of 6.
- Q23easy
What is the atomic number of Nitrogen
💡 Explanation:Nitrogen has an atomic number of 7.
- Q24easy
What is the atomic number of Helium
💡 Explanation:Helium has an atomic number of 2.
- Q25medium
Which element has the atomic number 79 and is famously used in jewelry and as a store of value
💡 Explanation:Gold has the atomic number 79.
- Q26easy
Which element has the highest natural abundance in the Earth's atmosphere
💡 Explanation:Nitrogen makes up approximately 78% of Earth's atmosphere, the most abundant atmospheric gas.
- Q27easy
Approximately what percentage of Earth's atmosphere is composed of oxygen
💡 Explanation:Oxygen constitutes approximately 21% of Earth's atmosphere.
- Q28medium
Which element is the most abundant in the Earth's crust by mass
💡 Explanation:Oxygen is the most abundant element in the Earth's crust by mass, primarily in the form of oxide compounds.
- Q29easy
Which is the lightest chemical element in the periodic table
💡 Explanation:Hydrogen is the lightest element in the periodic table.
- Q30medium
Which element is the most abundant in the entire observable universe
💡 Explanation:Hydrogen is the most abundant element in the universe, making up roughly 75% of its elemental mass.
- Q31easy
Who is credited with developing the first widely recognized periodic table, arranging elements by atomic weight
💡 Explanation:Dmitri Mendeleev developed the first widely recognized periodic table in 1869, arranging elements by atomic weight.
- Q32hard
What is the general name for the specific region within the periodic table containing elements with partially filled d-orbitals, including many industrially important metals
💡 Explanation:The d-block, containing the transition metals, includes many industrially significant metals like iron, copper, and gold.
- Q33easy
What is the chemical symbol for Calcium
💡 Explanation:Calcium's chemical symbol is Ca.
- Q34easy
What is the chemical symbol for Neon
💡 Explanation:Neon's chemical symbol is Ne, commonly known for its use in neon signs.
- Q35medium
What is the chemical symbol for Argon
💡 Explanation:Argon's chemical symbol is Ar.
- Q36medium
What is the chemical symbol for Titanium
💡 Explanation:Titanium's chemical symbol is Ti, known for its strength and lightweight properties.
- Q37medium
What is the chemical symbol for Cobalt
💡 Explanation:Cobalt's chemical symbol is Co.
- Q38medium
What is the chemical symbol for Manganese
💡 Explanation:Manganese's chemical symbol is Mn.
- Q39hard
What is the chemical symbol for Barium
💡 Explanation:Barium's chemical symbol is Ba.
- Q40medium
What is the chemical symbol for Iodine
💡 Explanation:Iodine's chemical symbol is simply I.
- Q41medium
What is the chemical symbol for Bromine
💡 Explanation:Bromine's chemical symbol is Br.
- Q42hard
What is the name for the two rows typically placed below the main body of the periodic table, including elements like uranium and plutonium
💡 Explanation:The Lanthanides and Actinides are typically placed below the main table body, including elements like uranium and plutonium.
- Q43medium
What is the chemical symbol for Fluorine
💡 Explanation:Fluorine's chemical symbol is simply F.
- Q44medium
Which element has atomic number 92, notable for its use in nuclear power and weapons
💡 Explanation:Uranium has atomic number 92 and is significant in nuclear energy and weapons applications.
- Q45medium
Which radioactive element, discovered by Marie and Pierre Curie, has the atomic number 88
💡 Explanation:Radium, discovered by the Curies, has atomic number 88.
- Q46hard
Which element, discovered by Marie Curie and named after her native country, has atomic number 84
💡 Explanation:Polonium, discovered by Marie Curie, was named after her native Poland and has atomic number 84.
- Q47medium
What is the term for atoms of the same element having different numbers of neutrons
💡 Explanation:Isotopes are atoms of the same element with the same number of protons but different numbers of neutrons.
- Q48medium
What is the term for different structural forms of the same element in the same physical state, such as diamond and graphite for carbon
💡 Explanation:Allotropes refer to different structural forms of the same element, such as diamond and graphite, both forms of carbon.
- Q49medium
Diamond and graphite are both allotropes of which element
💡 Explanation:Diamond and graphite are both allotropic forms of carbon, differing in their atomic structural arrangement.
- Q50medium
What is the term for a positively or negatively charged atom or molecule, resulting from loss or gain of electrons
💡 Explanation:An ion is an atom or molecule that has gained or lost electrons, resulting in a net electrical charge.
- Q51medium
What is the term for a negatively charged ion, having gained one or more electrons
💡 Explanation:An anion is a negatively charged ion, formed when an atom gains one or more electrons.
- Q52medium
What is the term for a positively charged ion, having lost one or more electrons
💡 Explanation:A cation is a positively charged ion, formed when an atom loses one or more electrons.
- Q53easy
Which subatomic particle carries a positive electrical charge, found in the nucleus of an atom
💡 Explanation:Protons carry a positive charge and are found within the atomic nucleus.
- Q54easy
Which subatomic particle carries no electrical charge, found in the nucleus alongside protons
💡 Explanation:Neutrons carry no electrical charge and reside in the nucleus alongside protons.
- Q55easy
Which subatomic particle carries a negative electrical charge and orbits the nucleus
💡 Explanation:Electrons carry a negative charge and orbit the nucleus in electron shells.
- Q56medium
What determines an element's atomic number
💡 Explanation:An element's atomic number is determined by the number of protons in its nucleus.
- Q57easy
What is the chemical symbol for Magnesium
💡 Explanation:Magnesium's chemical symbol is Mg.
- Q58easy
What is the chemical symbol for Aluminum
💡 Explanation:Aluminum's chemical symbol is Al.
- Q59easy
What is the chemical symbol for Zinc
💡 Explanation:Zinc's chemical symbol is Zn.
- Q60medium
What is the chemical symbol for Nickel
💡 Explanation:Nickel's chemical symbol is Ni.
- Q61easy
What is the chemical symbol for Chlorine
💡 Explanation:Chlorine's chemical symbol is Cl.
- Q62easy
What is the chemical symbol for Sulfur
💡 Explanation:Sulfur's chemical symbol is simply S.
- Q63medium
What is the chemical symbol for Platinum
💡 Explanation:Platinum's chemical symbol is Pt.
- Q64medium
What is the chemical symbol for Uranium
💡 Explanation:Uranium's chemical symbol is simply U.
- Q65easy
What is the chemical symbol for Phosphorus
💡 Explanation:Phosphorus's chemical symbol is simply P.
- Q66medium
Which element, added in trace amounts to municipal water in some areas, is credited with helping prevent tooth decay
💡 Explanation:Fluoride, a compound of fluorine, is added to some water supplies to help prevent tooth decay.
- Q67hard
Which alkali metal, symbol Cs, is used in atomic clocks due to its precise vibrational frequency
💡 Explanation:Cesium is used in atomic clocks because its vibrational frequency provides an extremely precise time standard.
- Q68hard
Which reactive nonmetal, symbol F, is the most electronegative element on the periodic table
💡 Explanation:Fluorine is the most electronegative element in the periodic table, meaning it has the strongest tendency to attract electrons.
- Q69easy
Which element, symbol K, is essential for nerve function and is found abundantly in bananas
💡 Explanation:Potassium, symbol K, is essential for proper nerve and muscle function and is abundant in foods like bananas.
- Q70easy
Which soft, silvery-white alkaline earth metal, essential for bone health, has the chemical symbol Ca
💡 Explanation:Calcium, symbol Ca, is essential for bone health and various physiological functions.
- Q71medium
Which element is the third most abundant in the Earth's crust, widely used in construction and packaging (as its metal or compounds)
💡 Explanation:Aluminum is the third most abundant element in Earth's crust and is widely used in construction and packaging.
- Q72medium
Which element, the second most abundant in the Earth's crust after oxygen, is a key component of sand, glass, and computer chips
💡 Explanation:Silicon is the second most abundant element in Earth's crust, essential to sand, glass, and semiconductor manufacturing.
- Q73medium
Which chemical element, symbol Ne, is a noble gas that does not naturally form compounds under normal conditions
💡 Explanation:Neon, a noble gas, is chemically inert and does not naturally form compounds under standard conditions.
- Q74hard
Which trace element, essential in small amounts for human health but toxic in excess, has the symbol Se
💡 Explanation:Selenium, symbol Se, is an essential trace element with antioxidant properties, though toxic in excessive amounts.
- Q75medium
Which semi-metallic element, symbol As, is highly toxic and has historically been used as a poison
💡 Explanation:Arsenic, symbol As, is a toxic semi-metallic element historically infamous for its use as a poison.
- Q76medium
Which highly toxic heavy metal, symbol Pb, was historically used in paint and gasoline before health concerns led to bans
💡 Explanation:Lead, symbol Pb, was historically used in paint and gasoline until health concerns led to widespread regulatory bans.
- Q77medium
Which lightweight, silvery metal, atomic number 3, is used in modern rechargeable batteries
💡 Explanation:Lithium, atomic number 3, is widely used in modern rechargeable batteries due to its light weight and electrochemical properties.
- Q78medium
Which metal, resistant to rust and commonly used in stainless steel, has the chemical symbol Cr
💡 Explanation:Chromium, symbol Cr, is added to steel to create stainless steel, providing rust resistance.
- Q79easy
Which noble gas, atomic number 10, is commonly used in illuminated signage due to its distinctive glow
💡 Explanation:Neon gas produces a distinctive reddish-orange glow when electrified, commonly used in neon signs.
- Q80medium
Which precious metal, resistant to corrosion, is commonly used in jewelry and has the chemical symbol Pt
💡 Explanation:Platinum, symbol Pt, is a corrosion-resistant precious metal commonly used in fine jewelry and industrial catalysts.
- Q81medium
Which element, atomic number 26, is a key component of steel and essential for hemoglobin
💡 Explanation:Iron (atomic number 26) is essential both as a component of steel and as a key part of hemoglobin.
- Q82medium
Which two elements combine to form the alloy steel, primarily
💡 Explanation:Steel is primarily an alloy of iron and carbon, with the carbon content affecting its properties.
- Q83medium
Which two elements combine to form the alloy bronze
💡 Explanation:Bronze is an alloy primarily composed of copper and tin.
- Q84medium
Which two elements combine to form the alloy brass
💡 Explanation:Brass is an alloy composed primarily of copper and zinc.
- Q85hard
Which gas, essential for combustion, was historically called "dephlogisticated air" before its proper identification
💡 Explanation:Oxygen was historically referred to as "dephlogisticated air" by early chemists before Lavoisier properly characterized it.
- Q86hard
Which scientist is credited with identifying and naming oxygen, establishing key principles of modern chemistry
💡 Explanation:Antoine Lavoisier is credited with correctly identifying and naming oxygen, foundational to modern chemistry, though Priestley also independently discovered it.
- Q87medium
Which scientist developed the early atomic theory, proposing that matter is composed of indivisible atoms
💡 Explanation:John Dalton developed early atomic theory, proposing that all matter is composed of indivisible atoms.
- Q88medium
Which chemical element, atomic number 6, exists in multiple forms including diamond, graphite, and more recently discovered fullerenes
💡 Explanation:Carbon exists in various allotropic forms, including diamond, graphite, and fullerenes like buckminsterfullerene.
- Q89medium
Which chemically inert element, atomic number 2, is used to cool superconducting magnets, including in MRI machines
💡 Explanation:Helium, due to its extremely low boiling point, is used to cool superconducting magnets in devices like MRI machines.
- Q90medium
Which element, atomic number 17, is used in small amounts to disinfect drinking water supplies
💡 Explanation:Chlorine (atomic number 17) is widely used to disinfect municipal water supplies.
- Q91medium
Which gas, symbol N, is used to create an inert atmosphere in food packaging to preserve freshness
💡 Explanation:Nitrogen gas is commonly used in food packaging to displace oxygen and preserve freshness.
- Q92medium
Which element, symbol Si, is the primary component of computer chips and glass
💡 Explanation:Silicon, an abundant metalloid, is the primary material used in computer chips and glass manufacturing.
- Q93hard
Which noble gas, symbol Xe, is used in some specialized lighting and ion propulsion for spacecraft
💡 Explanation:Xenon is used in specialized lighting and has applications in ion propulsion systems for spacecraft.
- Q94medium
Which radioactive noble gas, symbol Rn, can accumulate in basements and poses a health hazard
💡 Explanation:Radon is a radioactive noble gas that can accumulate in enclosed spaces like basements, posing lung cancer risks.
- Q95easy
Which metal, extremely lightweight and used in aircraft manufacturing, has the chemical symbol Al
💡 Explanation:Aluminum, symbol Al, is a lightweight, strong metal widely used in aircraft and other manufacturing applications.
- Q96easy
Which metal, known for being liquid at room temperature, has the chemical symbol Hg
💡 Explanation:Mercury, symbol Hg, is unusual among metals for being liquid at standard room temperature.
- Q97easy
Which element, essential for life and forming the backbone of organic molecules, has the chemical symbol C
💡 Explanation:Carbon, symbol C, forms the structural backbone of all organic molecules essential to life.
- Q98medium
Which highly reactive metal, stored in oil to prevent reaction with air/water, has the chemical symbol Na
💡 Explanation:Sodium, a highly reactive alkali metal, is typically stored in oil to prevent reaction with air or moisture.
- Q99hard
Which spherical carbon allotrope, resembling a soccer ball structure, was discovered in 1985 and later earned a Nobel Prize
💡 Explanation:Buckminsterfullerene, a spherical carbon molecule resembling a soccer ball, was discovered in 1985, earning a Nobel Prize.
- Q100medium
Which element is used as the primary fuel source in most nuclear power plants
💡 Explanation:Uranium, particularly the isotope U-235, is the primary fuel used in most conventional nuclear power plants.
- Q101hard
Which single-layer carbon allotrope, known for extraordinary strength and conductivity, was isolated in 2004, also earning a Nobel Prize
💡 Explanation:Graphene, a single layer of carbon atoms, was isolated in 2004 and earned researchers a Nobel Prize for its remarkable properties.