International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

Which property makes iron particularly suitable for construction purposes?

1. Flexible

2. Strong

3. Lightweight

4. Corrosion-resistant

The correct answer is: Strong

Iron is particularly suitable for construction purposes primarily because of its strength. This property enables it to support heavy loads and withstand various forces, making it an essential material in buildings, bridges, and other structures. The strength of iron allows it to maintain structural integrity and ensure safety in construction applications. While flexibility, lightweight characteristics, and corrosion resistance are important properties in certain contexts, they do not define iron's primary suitability for construction. For instance, while some flexibility can be beneficial in absorbing shocks, excessive flexibility can lead to structural weakness. Similarly, lightweight materials may be advantageous in some applications, but iron's strength outweighs the need for being lightweight in most structural contexts. Finally, while iron can be treated to improve corrosion resistance (e.g., through galvanization), raw iron is not inherently corrosion-resistant, which can limit its use in environments where exposure to moisture and other corrosive elements is a concern without protection. Thus, the inherent strength of iron is what truly makes it a cornerstone material in construction.