Question

Consider the reaction between 15.0 mL of a 1.00 M aqueous solution of AgNO3 and 10.0 mL of a 1.00 M aqueous solution of K2CrO4. When these react, a precipitate is observed. What is present in solution after the reaction is complete

Answer 1

Answer:

Species present in the solution after complete reaction: $K^+ ,CrO_4^- , Ag_2CrO_4 , K^+ ,NO_3^-$

Explanation:

First balance the chemical equation,

$2AgNO_3 + K_2CrO_4 =Ag_2CrO_4 + 2KNO_3$

calculation of mili moles of each:

$mili mole= volume in ml \times molarity$

mili mole of AgNO3= 15mili mole;

mili mole of K2CrO4=10 mili mole;

From balance equation,

2 mili mole  of AgNO3 reacts with 1 mili mole of K2CrO4

hence 1 mili mole  of AgNO3 reacts with 0.5 mili mole of K2CrO4

15 mili mole  of AgNO3 reacts with 7.5 mili mole of K2CrO4

so only 7.5 milimole will be used in the reaction and 2.5 mili mole left in solution.

species present in the solution after complete reaction:

$K^+ ,CrO_4^- , Ag_2CrO_4 , K^+ ,NO_3^-$

$K_2CrO4 , KNO_3$ are soluble in water so it will dissociate in the solution