Astudent is asked to balance an equation by using the half-reaction method. he determines the two half reactions as shown below. 2br- ➡️ br2+2e- cl2+2e-➡️2cl- what should he write as the final, balances equation ? cl2 +2br-➡️br2+2cl- cl2+2br-+2e-➡️br2+2cl- cl2+2br-➡️br2 +cl- + 2e- cl2 +br-+2e-➡️br2+cl-+2e-

2Br ⁻ ➡️ Br2+2e-

Cl2+2e-➡️2Cl⁻

Cl2 +2Br⁻➡️Br2 +2Cl⁻

Answer A.

- 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