A student does an experiment to determine the molar so… (2023)

The molar solubility of lead iodide is $1.45 \times 10^{-3} \mathrm{M}$ at $20^{\circ} \mathrm{C}$ and $6.85 \times 10^{-3} \mathrm{M}$ at $80^{\circ} \mathrm{C}$ . What are the values of $\Delta H^{\circ}$ and $\Delta S^{\circ}$ for dissolution of $\mathrm{PbI}_{2} ?$
$$\mathrm{PbI}_{2}(s) \longrightarrow \mathrm{Pb}^{2+}(a q)+2 \mathrm{I}^{-}(a q)$$
Assume that $\Delta H^{\circ}$ and $\Delta S^{\circ}$ are independent of temperature.

Let us assume the concentration off lead is X and the concentration off fired ideas. My diet is twice X as we know. K s P is a girl too. TV toe Plus my people, I'd buy iodide Yeah, x two i six in each tool. That's to all the Yes, we would be a key fee would be X multiplied by two a six square. We have the value off case he is 1.4 multiplied Britain toe the par minus eight. Is it going to x multiplied by twice X square, which is a quarter forex square. Therefore, the value off expert be 1.5 multiplied by 10 to the power minus tree more for later in, uh, and 0.1 more love BB and not say toe since we put extra lead into the system. So the concentration off lead cata inward way laedc Italian baby took plus with weight X plus 0.1 more and iodide and I would be same twice X. Therefore, S P is equal to TV two plus multiplied by I idea it. They're putting the values que species 1.4 multiplied. Better to depart minus eight TV Two places Express 0.1 and my diet ease Toys Square twice X squared. Therefore expert based 1.9 multiplied by 10 to the power minus four more spoke later uh, in 0.1 more. Also, sodium I died If we put their 0.1 mole off sodium iodide into the system than the concentration off you let Catan good Babe x But the concentration off I died and I end with beef twice X plus 0.0 one. Therefore, case P is equal to TV two plus I died negative where? Hey, he is 1.4. Multiply will tend to be four minus eight Ladies X on our divers twice expressed 0.1 more square by calculating every let us The value of X is very small So we a zoom value of iodide s off 1.4 tend to depart minus later on value off I had died would be 0.1 Where therefore X is equal to 1.4 multiplied Pretend to depart minus four more spoke late

This question was constant. Calculated availability of large Iowa died in different solvent. First year water. Let's let's assume they girls. Intrusion off blood is acts than the concentration off I'll guide on my own would be a two acts. So chaos p equals two acts times to access square. The axe is 1.252 times turned to the night in three. So question being there a point to one mullah this solvent on DDE because we put extra lead kite how into the into the system. So the concentration of lead kite i'il would be acts plus the over one. But the concentration off I owe died on ion doesn't change from this potion. Will you know X equals to 1.9 times 10 to the inactive for move more per liter if we put questions, see if we pull 0.0 overwhelm ola off sodium iodide in the system than the concentration off like that doesn't change is still acts, but the concentration off Iowa Guide and I only be two acts plus 0.1 B because axe is much smaller than their appointed everyone, so we can assume this equals to 0.1 square, so the axe equals to 1.4 times 10 to the negative for more.

Here we have two different reactions. One we have silver iodide associating into a G. Plus in hiding and nine. And the other reactions where we have uh silver ion reacting ceremonially into the formation of a complex science. So the net reaction is the sum of these two reactions. So this is the following. So for the first reaction, uh it's equally equilibrium constant can be determined from K. sp table. So this is equivalent to 8.5 times 10 to the -17. For the second reaction, the equilibrium constant can also be determined from a table. So this is 1.6 times 10 to the seventh. Yeah. And we can use this information to essentially determine our general equilibrium constant. Since we're adding both reactions together, we're going to be multiplying their equilibrium constants based on the rules. So this becomes that our equilibrium constant is equivalent to 1.36. So it would be 8.5 times sent 17 times. Okay? And we find that equilibrium constants about 1.36 Times 10 to the -9. And so silver iodide has a certain liability that dissolves in solution. Were given information that we're going to use 2.2 molar ammonia. So this is going to decrease by two times as much. There's an increase in the amount of uh the two uh the two ions. And as a result we can find that the scalability squared over 2.2 minus uh Following It's equivalent to 1.36 times 10 to the -9. And now we have we have to take the square root of both sides of the positive square, Leading us to find that 3.7 times 10 to the negative five is equivalent to the scalability over 2.2 -2 times the solid ability. Okay. Okay. And we can multiply out, yeah. Yeah. Okay. Okay. Mhm. Okay. As a result, we find that our final answer is equivalent. The scalability is about 8.1 times 10 to the negative five molars, and this gives our final answer.

Hi there. We have to calculate the suitability products off silver iodide in the potential of the silver electrodes immersed in tow. The situated silver iodide solution is 0.3 to 5 volts, four standard hydrogen electron, and the temperature is 298. Kevin. So we need to find the celebrity product. So first, let's start musically. Librium off silver iodide adequately room some off silver iodide it tiny fractions though he was dissolved, releasing silver ions and I dine irons to the solution. And meanwhile, the but electrochemical reduction off couple off silver A cures Yeah, due to the following equation. So silver iron gets one election and form silver medal the nurse but nursed equation for this reaction is the following. So the potential of this couple equals to the standard potential loss. Yeah, are tee divided by an F multiplied by the natural logarithm off concentration off Sylar or 0.8 walls plus are tee multiplied by F because on Lee won, election takes part in this reaction when multiplied by the concentration off. Sure, let's find the concentration of silver. So we know that this the measure potential is 0.325 volts, which equals to 0.8 vaults plus rt, divided by far the constant multiplied by the natural logarithm of the Consideration or Sylar. Therefore, natural logarithm of concentration off Sylar equals toe difference off the potentials multiplied by for the constant and divided by R t, which is Ah, negative 18.5. So therefore, the concentration off equilibrium concentration off silver equals toe exponents power by minus 18.5, which is quite low. So the equals toe 9.2 multiplied by 10 to the minus nine Mueller. So this is equilibrium, concentration off silver riots, innocent iterated, silver iodide solution. So now let's ah calculates ah scalability product. So the scalability product is a constant off this reaction. So scalability products equals toe the concentration off silver ions multiplied by the concentration off iodide ions. Or it's square concentration off silver ions because the consideration off silver ions equals to the consideration off iodide ions. So now we can calculate celebrity product so it equals to nine 0.2 multiplied by 10 to the minus nine Mueller all squared, which equals toe 8.52 multiplied by 10 power bi minus 17 malls squared. So are we cannot base the unit. So which gives us the following answer. So the scalability product off she'll where I die, this 8.52 multiplied by 10 to the minus 17. Yep. Thank you.