Choose the word which is different from the rest.

Iron
Nickel
Cobalt
Aluminum

The answer is D. Aluminum.

Iron, nickel, and cobalt are all ferromagnetic metals, meaning they are attracted to magnets. Aluminum is not ferromagnetic.

Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series and is the most common element (by mass) on Earth. It is a member of the iron group in the periodic table: a group of elements in the periodic table of the chemical elements that have a similar chemical behaviour. The atomic number of iron is 26, and it has a relative atomic mass of 55.845. Iron is a silvery-white metal that is found in the Earth’s crust in the form of iron ore. It is a very strong metal that is used in many different applications, including construction, machinery, and transportation.

Nickel is a chemical element with the symbol Ni and atomic number 28. It is a silvery-white metal that is found in the Earth’s crust in the form of nickel ore. It is a very strong metal that is used in many different applications, including coins, batteries, and jewelry.

Cobalt is a chemical element with the symbol Co and atomic number 27. It is a silvery-white metal that is found in the Earth’s crust in the form of cobalt ore. It is a very strong metal that is used in many different applications, including magnets, batteries, and jewelry.

Aluminum is a chemical element with the symbol Al and atomic number 13. It is a silvery-white metal that is found in the Earth’s crust in the form of aluminum ore. It is a very strong metal that is used in many different applications, including construction, machinery, and transportation. However, aluminum is not ferromagnetic. This means that it is not attracted to magnets.