---
title: "Define bitumen and tar"
subject: "Civil Engineering Materials"
chapter: 10
key: "semester_3/civil_engineering_materials:define-bitumen-tar"
source: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/define-bitumen-tar
site: BCT Engineering
---

# Define bitumen and tar

Civil Engineering Materials · Chapter 10: Asphalt, Bitumen, Tar and Miscellaneous Materials

- Asked in: 2071 Chaitra, 2 marks
- Video: [tar and bitumen | transportation engineering | civil engineering](https://www.youtube.com/watch?v=So8c5l-jA8E) — Civil Engineering CE
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/define-bitumen-tar
- Whole chapter: https://www.bctengineer.com/md/semester_3/civil_engineering_materials/chapter-10

## Question

Define bitumen and tar.

## Short answer

Bitumen is a black sticky hydrocarbon mixture from petroleum distillation or natural deposits, soluble in carbon disulphide, used as binder/waterproofing. Tar is a dark viscous liquid from destructive distillation of coal/wood, used for road dressing and timber preservation; it is more temperature-sensitive and less durable.

## Answer

**Bitumen** is a black or dark brown, sticky, waterproof mixture of hydrocarbons, obtained as the residue after distillation of crude petroleum or found as natural deposits. It is soluble in carbon disulphide and is used as a binder and waterproofing material in roads and roofs.

**Tar** is a dark brown to black viscous liquid obtained by destructive distillation of coal, wood or peat in the absence of air. It is used for road surface dressing, priming, and as a preservative for timber and pipes. It is more temperature-sensitive and less durable than bitumen.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Bitumen is obtained as what?
   A. Residue from crude petroleum distillation or natural deposits
   B. Coal distillate
   C. Wood tar
   D. Limestone
   Answer: A. Residue of crude distillation or natural deposits. (Key point: Bitumen origin)

2. Tar is made from coal, wood or peat in what conditions?
   A. Excess oxygen
   B. Absence of air (destructive distillation)
   C. Under water
   D. Cold
   Answer: B. Destructive distillation in absence of air. (Key point: Tar origin)

3. Compared with bitumen, tar is what?
   A. More temperature-sensitive and less durable
   B. Less sensitive
   C. More durable
   D. Same
   Answer: A. Tar is more temperature-sensitive and less durable. (Key point: Comparison)

## Related in Civil Engineering Materials

- [Bitumen versus tar](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Abitumen-vs-tar) — Civil Engineering Materials, chapter 10, asked 2×
- [Compare asphalt, bitumen and tar](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aasphalt-bitumen-tar-comparison) — Civil Engineering Materials, chapter 10, asked 2×
- [Define asphalt, bitumen and tar](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Adefine-asphalt-bitumen-tar) — Civil Engineering Materials, chapter 10, asked 2×
- [Uses of asphalt, bitumen, tar](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Auses-asphalt-bitumen-tar) — Civil Engineering Materials, chapter 10

## Related in other subjects

- [Types of bitumen and bituminous materials](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Abitumen-types) — Transportation Engineering I, chapter 6, asked 6×