Sodium fluoride (NaF) is added to drinking water in some municipalities to protect teeth against cavities. The idea is to convert hydroxyapatite, Ca10(PO4)6(OH)2, into more stable fluorapatite, Ca10(PO4)6F2. The molar mass of hydroxyapatite is 502 g/mol. What is the molarity of a 10.0 mg/L sodium fluoride solution

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

what is the question?