C. MATERIALS ERUPTED

1. Lava - smooth = pahoehoe, rough = aa 71 (both are Hawaiian terms)

2. Gases - at high pressure gases (like H2O and CO2) are dissolved in magma. When magma rises through the crust, P decreases, gases undissolve (mostly H2O).

3. Crystals that form as magma cools.

4. Pyroclastic materials - in explosive eruptions, pulverized lava, pumice, and rocks are erupted.

Fine particles = ash 68, 77

larger = cinders and bombs 72

solidified volcanic froth = pumice

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