there is none
You die!
People in volcanoes may die and will lose their homes/land when the Volcano erupts.
No. Mercury is a geologically dead planet. It has no volcanoes, not atmosphere, and no water.
Volcanoes mostly erupt in the sea to make islands or big massesof land,
Volcanoes are not biological therefore do not 'live' anywhere.
Most rocky planets have hot interiors capable of melting rock and forming volcanoes, at least at some points in their existence. Water, however, requires the right surface conditions. Venus, due to its proximity to the sun and runaway greenhouse effect, is too hot for water. Mars is too cold for liquid water.
good for growing crops
secrete
Lots and lots of burning.
Water.
All volcanoes emit water vapor and other gases.