Why is energy required to break a covalent bond

Energy is required to break a covalent bond as a result of its necessity in the

formation of products.

Atoms in a covalent bond are usually much stable as a result of them

achieving the octet configuration. Energy is thereby required to break the

bonds in order to permit the interaction of the electrons of the substances

involved.

The interaction of the electrons is what acts as a precursor in the formation

of new products.

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aquifers are bounded above and below by impermeable rock. the driving force of groundwater movement in confined aquifers is pressure, rather than gravity.

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.