When sodium metal is placed in a flask full of chlorine gas, a violent reaction occurs. These dangerous non-charged elements, when mixed,
produce the ionic compound sodium chloride, otherwise known as table salt. Explain how this happens in terms of nuclei, electrons, and charges.

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.