Consider the following :
- 1.Pyroclastic debris
- 2.Ash and dust
- 3.Nitrogen compounds
- 4.Sulphur compounds
How many of the above are products of volcanic eruptions ?
Show answer
Answer: D. Volcanic eruptions throw out pyroclastic debris (broken rock fragments), ash and dust, and gases. These gases include water vapour, carbon dioxide, nitrogen compounds and sulphur compounds such as sulphur dioxide. So all four are products of eruptions.
Watch for: Students remember sulphur gases but forget that nitrogen compounds are also part of volcanic gases.
Why the other options are wrong
- A. Wrong because ash, debris and gases are all ejected, not just one item.
- B. Wrong because both gas types are released along with solid material.
- C. Wrong because nitrogen and sulphur compounds are both volcanic gases.
Source to check: NCERT Class 11 Fundamentals of Physical Geography, Chapter 3 'Interior of the Earth' (Volcanoes and Volcanic Landforms)
Answer from the official UPSC key. Written and fact-checked by AI against the official key. Spotted a mistake? Report it.