How many liters of nh3 are needed to react completely with 30.0 l of no (at stp)? 4nh3(g) + 6no(g) → 5n2(g) + 6h2o(g)?

20.0 L
That is your answer 

That result from subduction of oceanic plates beneath lighter continental plates. most of the earth's volcanoes are located around the pacific ring of fire because that the location of most of the earth's subduction zones.

10.063g / 10.00 ml = 1.0063 g/ml which rounds off to 4 sig figs as: 1.006 g/ml