Answer:
pretty sure it's C,
Explanation:
Mantle convection is the very slow creeping motion of Earth's solid silicate mantle caused by convection currents carrying heat from the interior to the planet's surface. ... This hot added material cools down by conduction and convection of heat.
The answer is Option C (Divergent Plate Boundary)
Mapping efforts have shown that mid-ocean ridges<span> are discontinuous structures that cut at </span>right angles<span> to its length at various transform faults. They typically </span><span>demarcate the </span>boundary <span>between two tectonic plates, and are therefore called </span>divergent<span> plate </span>boundaries.
Take mass of zinc divided by the relative molecular mass - 30 for zinc ( from periodic table)
Explanation:
Bayer process is industrial method of the refining of the bauxite to produce alumina which is aluminum oxide.
As alumina is amphoteric in nature, it exhibits a higher solubility at both the extremes of pH range, it is possible to dissolve alumina in low as well as in high pH solutions.
Dissolution of the alumina at high pH is well recognized in Bayer process. Bauxite is digested in very <u>high pH solution (> 13) of alkali</u> like sodium hydroxide at temperature of about 150–250°C and pressure at 20 atm. <u>This is done so that the dissolved alumina is separated from rest of insoluble bauxite minerals. </u>
