Suppose 0.780 of potassium iodide is dissolved in 150. mL of a 51.0mM aqueous solution of silver nitrate.
Calculate the final molarity of iodide anion in the solution. You can assume the volume of the solution doesn't change when the potassium iodide is dissolved in it.
Be sure your answer has the correct number of significant digits.
What does 0.780 stand for????
To calculate the final molarity of iodide anion in the solution, we need to use the concept of stoichiometry and the given information.
First, let's convert the volume of the solution to liters:
150 mL = 150/1000 L = 0.150 L
Next, let's use the molarity of the silver nitrate solution to calculate the number of moles of silver nitrate present:
Molarity = moles of solute / volume of solution
51.0 mM = (moles of silver nitrate) / 0.150 L
To find the moles of silver nitrate, we can rearrange the equation:
moles of silver nitrate = Molarity * volume of solution
moles of silver nitrate = 51.0 mM * 0.150 L
Now, we need to use the balanced chemical equation between silver nitrate (AgNO3) and potassium iodide (KI) to determine the stoichiometry of the reaction. The balanced equation is:
AgNO3 + KI → AgI + KNO3
From the equation, we can see that 1 mole of silver nitrate reacts with 1 mole of potassium iodide to produce 1 mole of silver iodide. Therefore, the number of moles of iodide anion (I-) is equal to the number of moles of silver nitrate.
Finally, we can calculate the moles of iodide anion:
moles of iodide anion = moles of silver nitrate = 51.0 mM * 0.150 L
To find the final molarity of iodide anion, we divide the moles of iodide anion by the final volume of the solution. Since we assumed the volume of the solution does not change, the final volume is still 0.150 L.
Now, we can calculate the final molarity of iodide anion:
Molarity of iodide anion = moles of iodide anion / final volume of solution
Molarity of iodide anion = (51.0 mM * 0.150 L) / 0.150 L
After canceling out the units, we find that the final molarity of iodide anion in the solution is 51.0 mM.