Question map
Which one of the following elements is used in pencil-lead ?
Explanation
The core of a modern pencil, commonly referred to as 'lead', is actually composed of graphite, which is a crystalline form of the element carbon [1]. Graphite consists of carbon atoms arranged in hexagonal arrays that form flat layers [1]. These layers are held together by weak forces, allowing them to slide over one another and onto paper when pressure is applied during writing [1]. Historically, graphite was mistaken for a form of lead due to its similar appearance and ability to leave dark marks, leading to the misnomer 'pencil lead'. In modern manufacturing, graphite is typically mixed with clay to adjust the hardness and darkness of the pencil; a higher proportion of clay results in a harder lead that produces lighter marks. Despite the name, pencils contain no actual metallic lead.
Sources
- [1] Science , class X (NCERT 2025 ed.) > Chapter 4: Carbon and its Compounds > Allotropes of carbon > p. 61