Final answer:
To determine the concentration of potassium ions after mixing the solutions, moles of potassium are conserved during the dilution process. The exact final concentration calculated is 1.33 M, which is not in the provided options. Nevertheless, the closest match would be 1.25 M.
Step-by-step explanation:
When mixing 25ml of a 2.0M solution of potassium sulfide with 50ml of a 1.5M zinc acetate, the goal is to determine the concentration of the potassium ion after mixing. To find this out, we need to apply the concept of dilution and conservation of moles.
To begin, let's calculate the initial moles of potassium in the potassium sulfide solution:
Moles of K+ = Molarity of K2S × Volume of K2S
= 2.0 M × 0.025 L = 0.050 moles
Note that in potassium sulfide (K2S), there are 2 moles of K+ for every mole of K2S, therefore we double the moles of K+:
Moles of K+ = 0.050 moles × 2
= 0.100 moles
The total volume after mixing is the sum of the individual volumes:
Total Volume = Volume of K2S + Volume of Zn(CH3COO)2
= 0.025 L + 0.050 L = 0.075 L
Finally, to find the final concentration of K+, we use:
Final concentration of K+ = Moles of K+ / Total Volume
= 0.100 moles / 0.075 L
= 1.33 M
Since 1.33 M is not one of the provided options, there may be a mistake in the question or answer choices. If we round to the nearest offered option, it would be 1.25 M (Option 3), but please note that the exact calculation gives 1.33 M.