Question #42189
1 Answer
Explanation:
Start by taking a look at the balanced chemical equation for this single replacement reaction
#"Zn"_text((s]) + color(red)(2)"Au"("NO"_3)_text(3(aq]) -> 2"Au"_text((s]) + 3"Zn"("NO"_3)_text(2(aq])#
The key to this problem is the
Your goal now is to figure out exactly how many moles of each reactant you're mixing. To do that, use zinc's molar mass and the molarity and volume of the gold(III) nitrate solution.
For zinc metal, you'll have
#1.00color(red)(cancel(color(black)("g"))) * "1 mole Zn"/(65.38color(red)(cancel(color(black)("g")))) = "0.01530 moles Zn"#
For gold(III) nitrate, you'll have
#color(blue)(c = n/V implies n = c * V)#
#n = "0.0500 M" * 50.0 * 10^(-3)"L" = "0.00250 moles Au"("NO"_3)_3#
It looks like you don't have enough moles of gold(III) nitrate to allow for all the moles of zinc to react. More specifically, the
#0.00250color(red)(cancel(color(black)("moles Au"("NO"_3)_3))) * "1 mole Zn"/(color(red)(2)color(red)(cancel(color(black)("moles Au"("NO"_3)_3)))) = "0.00125 moles Zn"#
out of the total
Now, the
Since
To determine how many grams of gold would contain this many moles, use gold's molar mass
#0.00250color(red)(cancel(color(black)("moles Au"))) * "196.97 g"/(1color(red)(cancel(color(black)("mole Au")))) = color(green)("0.492 g Au")#