The electrons which are primarily responsible for chemical bonds are:

the outer s subshell
the outer p subshell
the valence electrons
electrons with high ionization energy

The electrons which are primarily responsible for chemical bonds are the valence electrons. Atoms form two types of bonds: ionic bond and covalent bond. In a covalent bond, valence electrons are shared; in an ionic bond, valence electrons are transferred.

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms

the ratio of the conjugate base to the acid required to attain the desired ph.