Question

In this stoichiometry problem, determine the limiting reactant:

Aqueous copper(II) nitrate reacts with aqueous sodium sulfide to produce aqueous sodium nitrate and copper(II) sulfide as a precipitate. In this reaction 469 grams of copper(II) nitrate were combined with 156 grams of sodium sulfide to produce 272 grams of sodium nitrate. Select all that apply.

Answer 1

The limiting reactant : Na₂S

Further explanation

Reaction

Cu(NO₃)₂ (aq) + Na₂S (aq) ⇒ 2 NaNO₃ (aq) + CuS (s)

mol Cu(NO₃)₂ :(MW 187,56 g/mol)

$\tt mol=\dfrac{469}{187.56}=2.5$

mol Na₂S :(MW 78,0452 g/mol)

$\tt mol=\dfrac{156}{78.0452}=2.0$

Limiting reactant(smaller ratio⇒ between mol and coefficient) :

1 mol Cu(NO₃)₂ : 1 mol Na₂S , so the limiting reactant : Na₂S( 2 < 2.5)