The softest mineral on the mohs hardness scale is a. quartz. b. talc. c. apatite. d. gypsum.

The correct answer is Talc.

According to the Mohs hardness scale, the softest mineral is Talc which has a rating of one. This scales decides the hardness of the minerals. The Ability of all the other minerals to scratch talc makes it softest mineral. The hardness of the mineral are controlled partly by the size of the atoms and by the bonding between the atom.

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.