The heating curve below represents a sample of
a substance starting as a solid below its melting
point and being heated over a period of time.
which statement describes the energy of the
particles in this sample during interval de?

(1) both potential energy and average kinetic
energy increase.
(2) both potential energy and average kinetic
energy decrease.
(3) potential energy increases and average
kinetic energy remains the same.
(4) potential energy remains the same and
average kinetic energy increases.

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).