Answer:
0.10M of Ba²⁺ is the concentration of the metal in excess
Explanation:
Based on the chemical reaction:
K₂CO₃(aq) + Ba(NO₃)₂(aq) → BaCO₃(s) + 2KNO₃(aq)
<em>1 mole of potassium carbonate reacts per mole of barium nitrate</em>
<em />
To solve this question we need to find the moles of each salt to find then the moles of Barium in excess:
<em>Moles K₂CO₃:</em>
0.025L * (0.25mol / L) = 0.00625moles K₂CO₃ = moles CO₃²⁻
<em>Moles Ba(NO₃)₂:</em>
0.030L * (0.40mol/L) = 0.012 moles of Ba(NO₃)₂ = 0.012 moles of Ba²⁺
That means moles of Ba²⁺ that don't react are:
0.012 mol - 0.00625mol = 0.00575 moles Ba²⁺
In 25 + 30mL = 55mL:
0.00575 moles Ba²⁺ / 0.055L =
<h3>0.10M of Ba²⁺ is the concentration of the metal in excess</h3>