Question

g Given that 50.0 mL of 0.100 M magnesium bromide reacts with 13.9 mL of silver nitrate solution according to the unbalanced equation MgBr21aq2 AgNO31aq2 S AgBr1s2 Mg1NO3221aq2 (a) What is the molarity of the AgNO3 solution

Answer 1

Answer:

0.719M AgNO₃

Explanation:

Based on the reaction:

MgBr₂ + 2AgNO₃ ⇄ 2AgBr + Mg(NO₃)₂

1 mole of magnesium bromide reacts completely with 2 moles of AgNO₃

To find molarity of AgNO₃ solution we need to determine moles of AgNO₃ and, as molarity is the ratio of moles over liter (13.9mL = 0.0139L). Now, to determine moles of AgNO₃ we need to use the reaction, thus:

Moles AgNO₃:

Moles of MgBr₂ are:

50.0mL = 0.050L * (0.100mol / L) = 0.00500 moles of MgBr₂.

As the silver nitrate reacts completely and 2 moles of AgNO₃ reacts per mole of MgBr₂:

0.00500 moles MgBr₂ * (2 moles AgNO₃ / 1 mole MgBr₂) =

0.0100 moles of AgNO₃ are in the solution.

And molarity is:

0.0100 moles AgNO₃ / 0.0139L =

0.719M AgNO₃