How would I determine how many grams of antimony would form from the reaction of carbon with #"3.6 g"# of antimony(III) oxide?

1 Answer

Answer:

Use dimensional analysis (a.k.a. the factor-label method)

Explanation:

given: #3.6"g "Sb_2O_3#
reacts with carbon (C)
want: mass of Sb

#Sb_2O_3 + 3C rarr 2Sb + 3CO#

Setup a Dimensional analysis starting with the given over 1:

#(3.6"g "Sb_2O_3)/1#

Multiply by the molar mass conversion factor for #Sb_2O_3#:

#(3.6"g "Sb_2O_3)/1(1"mol "Sb_2O_3)/(291.5"g "Sb_2O_3)#

From the equation we see that 1 mole of #Sb_2O_3# produces 2 moles of #Sb# so we multiply by that conversion factor:

#(3.6"g "Sb_2O_3)/1(1"mol "Sb_2O_3)/(291.5"g "Sb_2O_3)(2"mol "Sb)/(1"mol "Sb_2O_3)#

Multiply by the conversion factor for the molar mass of #Sb#:

#(3.6"g "Sb_2O_3)/1(1"mol "Sb_2O_3)/(291.5"g "Sb_2O_3)(2"mol "Sb)/(1"mol "Sb_2O_3)(121.76"g "Sb)/(1"mol "Sb)#

Please observe that the units cancel; leaving only the units #"g "Sb#

#(3.6"g "Sb_2O_3)/1(1"mol "Sb_2O_3)/(291.5"g "Sb_2O_3)(2"mol "Sb)/(1"mol "Sb_2O_3)(121.76"g "Sb)/(1"mol" Sb) = 3.0"g "Sb larr#
answer