1
The chemical symbol of gold is:
Correct answer: D. Au
Au comes from the Latin word "aurum". Ag (from "argentum") is silver.
easy
Chemistry in Daily Life MCQs
Solved Everyday Science MCQs on chemical symbols, common compounds and formulas, acids and bases, metals and gases used in daily life.
25 MCQsUpdated 27 October 2026
Chemistry is all around us. These MCQs cover element symbols, common compounds such as baking soda and washing soda, acids in vinegar, lemons and the stomach, rusting, gases in balloons and fuels, and hard water.
Most questions link a chemical name to something familiar at home. Remembering that everyday link, for example vinegar and acetic acid, is easier than memorising formulas on their own.
- 2
The chemical symbol of iron is:
Correct answer: B. Fe
Fe comes from the Latin "ferrum". Ir is iridium and I is iodine.
easy - 3
The chemical symbol Na stands for:
Correct answer: D. Sodium
Na comes from the Latin "natrium" for sodium. Nitrogen is N, neon is Ne and nickel is Ni.
easy - 4
The chemical symbol of lead is:
Correct answer: A. Pb
Pb comes from the Latin "plumbum", which is also the origin of the word "plumber".
medium - 5
The chemical symbol K stands for:
Correct answer: C. Potassium
K comes from the Latin "kalium" for potassium. Krypton is Kr, calcium is Ca and phosphorus is P.
easy - 6
Which metal is liquid at room temperature?
Correct answer: C. Mercury
Mercury (Hg) is the only metal that is liquid at ordinary room temperature.
easy - 7
The chemical name of baking soda is:
Correct answer: B. Sodium bicarbonate
Baking soda is sodium bicarbonate (NaHCO₃). It releases carbon dioxide when heated or mixed with acid, which makes dough rise.
Read detailseasy - 8
The chemical formula of ozone is:
Correct answer: A. O₃
Ozone has three oxygen atoms. The ozone layer in the stratosphere absorbs harmful ultraviolet radiation.
easy - 9
A solution with a pH of 7 is:
Correct answer: B. Neutral
On the pH scale, 7 is neutral, below 7 is acidic and above 7 is basic (alkaline). Pure water at 25 °C has a pH of 7.
easy - 10
Vinegar contains which acid?
Correct answer: A. Acetic acid
Vinegar is a dilute solution of acetic acid, usually about 4–8%.
easy - 11
The sour taste of lemons and oranges is mainly due to:
Correct answer: D. Citric acid
Citrus fruits get their sharp taste mainly from citric acid.
easy - 12
Which acid is produced in the human stomach to help digestion?
Correct answer: B. Hydrochloric acid
The stomach lining secretes hydrochloric acid, which helps digest proteins and kills many microbes.
easy - 13
Rust is chemically:
Correct answer: B. Iron oxide (hydrated)
Rust forms when iron reacts with oxygen and water, producing hydrated iron(III) oxide.
easy - 14
The most abundant element in the Earth's crust is:
Correct answer: C. Oxygen
Oxygen makes up about 46% of the crust by mass, mostly in silicate rocks. Silicon is second.
medium - 15
The most abundant metal in the Earth's crust is:
Correct answer: B. Aluminium
Aluminium makes up about 8% of the crust by mass, more than any other metal. Iron is second.
medium - 16
Which gas is used to fill party balloons and airships because it is light and non-flammable?
Correct answer: A. Helium
Helium is lighter than air and does not burn. Hydrogen is lighter still but highly flammable.
easy - 17
Nitrous oxide (N₂O) is commonly known as:
Correct answer: B. Laughing gas
Nitrous oxide is called laughing gas because of the euphoria it can cause. It is used as a mild anaesthetic.
easy - 18
Compressed natural gas (CNG) consists mainly of:
Correct answer: A. Methane
Natural gas is mostly methane (CH₄). LPG is mainly propane and butane.
medium - 19
"Dry ice" is the solid form of:
Correct answer: D. Carbon dioxide
Dry ice is frozen CO₂. At normal pressure it turns straight from solid to gas (sublimation) at −78.5 °C.
easy - 20
The atomic number of an element equals the number of:
Correct answer: A. Protons in its nucleus
The atomic number is the number of protons. Protons plus neutrons give the mass number.
easy