You have 75.0 mL of a 2.50 M solution of Na2CrO4 (aq). You also have 125 mL of a 2.15 M solution of AgNO3 (aq). Calculate the concentration of NO3 when the two solutions are added together.
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To calculate the concentration of NO3 when the two solutions are added together, we need to determine the moles of NO3 in each solution and then add them together.
First, let's calculate the moles of Na2CrO4:
Moles of Na2CrO4 = concentration (in mol/L) × volume (in L)
= 2.50 mol/L × 0.075 L
= 0.1875 mol
Second, let's calculate the moles of AgNO3:
Moles of AgNO3 = concentration (in mol/L) × volume (in L)
= 2.15 mol/L × 0.125 L
= 0.26875 mol
Now, we add the moles of NO3 from both solutions together:
Total moles of NO3 = moles of Na2CrO4 + moles of AgNO3
= 0.1875 mol + 0.26875 mol
= 0.45625 mol
Next, we calculate the total volume after mixing both solutions:
Total volume = volume of Na2CrO4 + volume of AgNO3
= 0.075 L + 0.125 L
= 0.2 L
Finally, we can calculate the concentration of NO3 in the mixed solution:
Concentration of NO3 = Total moles of NO3 / Total volume
= 0.45625 mol / 0.2 L
= 2.28125 mol/L
Therefore, the concentration of NO3 when the two solutions are added together is approximately 2.28 M.