In the field of chemistry, one type of chemical is seen by many as something that nobody ever wants to be in a room with: hydrofluoric acid, HF. Only a handful of
chemists in the world utilize HF to perform specific experiments in regards to fluorine
centered chemistry. This fear stems from the scenario of hydrofluoric acid coming in
contact with calcium found in bones. The process in which this occurs is shown in the
balanced chemical equation below:
Ca3(PO4)2 (s) + 6 HF(aq) → 3 CaF2(aq)→ 3 CaF2 (aq) + 2 H3PO4 (aq)
Using your knowledge of periodic trends and ionic activity, create a CER
(Claim - Evidence - Reasoning) why fluorine would rather bind to calcium than
hydrogen as posed in the balance chemical equation above. You must include at
least two pieces of evidence from the periodic table, your scientific notebook, or other

- 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

a