Balance the reaction. a coefficient of "1" is understood. choose option "blank" for the correct answer if the coefficient is "1." al + o2 → al2o3

Balanced chemical reaction: 4Al + 3O₂→ 2Al₂O₃.

a) Oxidation half-reaction: Al⁰ → Al⁺³ + 3e⁻ /×4; 4Al⁰ → 4Al⁺³ + 12e⁻.

b) Reduction half-reaction: 4e⁻ + O₂ → 2O⁻² /×3; 12e⁻ + 3O₂ → 6O⁻².

Oxidation is increase of oxidation number, aluminium change oxidation number from zero to +3 and reduction is decrease of oxidation number, oxygen from 0 to -2.

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

14 days is the half-life of phosphorus-32