Question

The lead of lead pencils is not Pb but is:
(A) Calcium carbonate
(B) Iron
(C) Calcium sulphate
(D) Graphite

Answer 1

Hint: (1) A pencil is a tool used for writing and drawing purposes. It consists of a solid core inside a protective casing so that the core is prevented from being broken down.
(2) The core of lead pencils is an allotrope of carbon. Carbon has many allotropes, three of which are diamond, graphite and fullerenes.
Complete step by step answer: Most of the pencil cores consist of graphite powder mixed with clay. The so-called traditional lead pencils are actually graphite pencils. When a graphite pencil is used for writing, it leaves behind either black or grey marks that can be easily erased by erasers but are resistant to chemicals and moisture and natural aging. In the graphite pencil or lead pencil, the core is made up of thin graphite encased inside a shell of other material. This shell of other material is mostly made up of wood, but sometimes it is also made of plastic or recycled paper.
When a large scale deposit of graphite was found way back in 1565, it was so pure and solid that it was initially thought to be a form of lead. As a result, the pencil core was referred to as a lead and it is still being referred to as such in the present time. Hence, it is common for people to have the misconception that the core in the pencil is made up of lead even though it never actually contained the element ‘lead’ or ‘Pb’.

So, the lead in lead pencils is not actually the element lead, but is actually a graphite core. So, the correct option is option D.

Note: The pencil used in earlier times contained natural graphite but the modern day pencil consists of a combination of graphite powder mixed with clay. The graphite pencils are the most commonly used pencils as they give smooth strokes. Some other types of commonly used pencils are charcoal pencils, carbon pencils, coloured pencils and watercolor pencils. The shapes of pencils may be round, hexagonal or triangular.