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?

1. Only one
2. Only two
3. Only three
4. All four

Explanation

Option (d) is correct

• Volcanic eruptions discharge various materials, including gases, vapours, lavas, fragmental materials, dust and ashes. Vapours and gases account for 60 to 90 per cent of emissions. Volcanic gases consist of carbon dioxide, nitrogen oxides, sulfur dioxide, hydrogen, and carbon monoxide, along with compounds like sulfurated hydrogen, hydrochloric acid, and volatile chlorides of iron, potassium, and other metals. Various categories of pyroclastic material are ejected during an eruption, including tephra (ash), volcanic dust, lapilli, and volcanic bombs.

Answer: (d) All four; Difficulty Level: Easy