Animated Solution for Chemistry - d and f-Block Elements: Mischmetal is an alloy consisting mainly of

Have you ever sparked a cigarette lighter or a gas striker and wondered what creates that brilliant, hot spark? The secret lies in a fascinating material called Mischmetal.

In the world of f-block elements, lanthanoids often seem like a mysterious group of metals sitting quietly at the bottom of the periodic table. But they have some incredibly practical applications in our daily lives and in heavy industries. One of the most famous applications is the creation of Mischmetal.

So, what exactly is Mischmetal? The name itself comes from German, meaning "mixed metal." It is an alloy, but not just any ordinary alloy. It is composed almost entirely of lanthanoid metals.

If we look at its exact composition, it contains approximately $95\%$ lanthanoids. Among these lanthanoids, Cerium (Ce) takes the lion's share at about $50\%$, followed by Lanthanum (La) at around $40\%$, with the remaining $5\%$ being a mix of other lanthanoids like Neodymium and Praseodymium.

But a pure lanthanoid alloy would be too soft for many applications. To give it structural integrity and specific properties, about $5\%$ Iron (Fe) is added. You will also find tiny traces of elements like Sulfur (S), Carbon (C), Calcium (Ca), and Aluminum (Al).

When Mischmetal is alloyed with iron, it forms a "pyrophoric" alloy. This means that when it is scratched or struck, it produces sparks. This is exactly why it is the primary material used in the "flints" of lighters!

Beyond making fire, Mischmetal plays a crucial role in metallurgy. It is added to steel to remove impurities like oxygen and sulfur, significantly improving the strength and workability of the final steel product.

Returning to our question, it asks what Mischmetal mainly consists of. Given that $95\%$ of its mass is made up of elements from the lanthanide series, the answer is crystal clear. It does not contain actinoids, which are generally radioactive and unsuitable for such everyday commercial alloys.

Therefore, Mischmetal is an alloy consisting mainly of lanthanoid metals.