A fan.
(Specific) heat capacity.
Basalt cools off quickly because it is formed under water.
Lava will cool quickly compared to underground magma.
When lave cools fairly quickly, but not instantaneously, the rock that is producing will have small or nearly invisible crystalsform.
Specific heat capacity is the amount of energy required to increase the temperature of an object or substance by 1oK. The rate at which something cools is proportional to the difference in temperature between the object and its surroundings. Consequently, neither has any relation to the other.
It cools quickly.
it explodes
"Larger than if it cools quickly" is about all that's definitively possible to say.
Small
No. Granite cools from magma deep underground. Volcanic glass cools quickly at or near the surface.
Lava cools quickly and forms rocks with small crystals. They are called extrusive igneous rocks.
It is true that lava cools quickly and forms minerals with small crystals.