10. a rock that forms from cooling lava is classified as an a. extrusive igneous rock b. extrusive metamorphic rock c. intrusive igneous rock d. intrusive volcanic rock

The best answer is:

a. Extrusive igneous rocks

In general, rocks that are formed by the cooling of magma are classified as igneous rocks. The key word however in this case is "lava," which is magma that reached the surface. This is what makes it an extrusive igneous rock, because it formed in the surface.

answer: -

reaction:

na + cl ⇌ nacl

balanced chemical equation:

na + 2cl ⇌ nacl2

sodium + clorine goes to form sodium chloride (table salt).

the product is nacl2.

and the reactants are na and cl.

(note: if you don’t know what ⇌ means, read below: -

⇌(double head arrow) means reversible reaction).

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).