Which of these does not belong to the group?

The correct answer is Mercury.

Key Points

• Mercury is a chemical element with the symbol Hg and atomic number 80.
• It is the only metallic element that is liquid at standard conditions for temperature and pressure.
• Mercury is a poor conductor of heat but a fair conductor of electricity.
• The other elements listed (Iron, Copper, Aluminium) are all solid metals at room temperature.

Additional Information

• Iron (Fe)
  • Iron is a chemical element with the symbol Fe and atomic number 26.
  • It is the most common element on Earth by mass and forms much of Earth's outer and inner core.
  • Iron is a key component in the production of steel and is used extensively in construction and manufacturing.
• Copper (Cu)
  • Copper is a chemical element with the symbol Cu and atomic number 29.
  • It is known for its high thermal and electrical conductivity.
  • Copper is widely used in electrical wiring, plumbing, and the manufacturing of electronics.
• Aluminium (Al)
  • Aluminium is a chemical element with the symbol Al and atomic number 13.
  • It is noted for its low density and ability to resist corrosion.
  • Aluminium is used in a variety of industries including aerospace, construction, and consumer goods due to its lightweight and durability.