In the second step of airbag deployment, sodium oxide (Na20) and iron
(Fe) are produced from sodium (Na) and ferric oxide (Fe203). How many
grams of sodium metal are required to produce 0.5 mol of iron (Fe) in the
reaction? (The molar mass of Na = 23 g/mol. Enter a numeric answer
only with no units. Show your answer to two digits after the decimal. All
other formats will be counted wrong.)
However, this reaction does not inflate the bag enough, and the sodium
metal is dangerously reactive. Oxidizers such as ferric oxide, Fe2O3, are
included, which react rapidly with the sodium. Energy is released, which
heats the gas and causes the gas to expand and fill the bag.
6Na(s) + Fe2O3(s)3Na2O(s)+2Fe(s) + energy
One product, sodium oxide, Na2O, is extremely corrosive. Water vapor
and CO2 from the air react with it to form less harmful NaHCO3.
Na₂O(s) + 2CO2(g) + H2O(g) →→2NaHCO3(s)
The mass of gas needed to fill an air bag depends on the density of
the gas. Gas density depends on temperature. To find the amount of gas
generant to put into each system, designers must know the stoichiometry
of the reactions and account for changes in temperature and thus the
density of the gas.
10 poim