Chemistry SAT II question

<p>Here are some of the Chemistry questions I got wrong, and that I don't know how to do (These came from BB):</p>

<p>44.) Which of the following statements is true concerning a saturated solution of a salt at a constant temperature?</p>

<p>(A) The concentrations of salt and solvent are usually equal.
(B) The amount of dissolved salt is constant.
(C) Addition of solid salt shifts the equilibrium, which results in an increase in amount of dissolved salt.
(D) The solution is unstable and sudden crystallization could occur.
(E) At the same temperature, a saturated solution of any other salt has the same concentration.</p>

<p>[I chose (D) because in Chemistry class I remembered an experiment where we added salt to a supersaturated solution, and crystals were formed]</p>

<p>48.) An active ingredient in common household bleach solutions is most likely to be which of the following?</p>

<p>(A) NaCl
(B) NaClO
(C) NaHCO3
(D) Na2SO4
(E) HC2H3O2</p>

<p>[I chose (E) because I thought it could have been a base, and bases are usually cleaning products]</p>

<p>Thanks for all the help and explanations!</p>

<ol>
<li><p>Recall that at saturated conditions the aqueous amounts of salt is exactly balanced with the amount that the solvent can hold. Your answer describes a SUPERsaturated solution which is not the same as a plain ole saturated solution. The answer is (B)</p></li>
<li><p>Eliminate the wrong answer choices. In order of appearance: salt, sodium hypoclorite, sodium bicarbonate sodium sulfate, acetic acid. (a), (d), and (e) are obviously wrong. The correct answer is (b).</p></li>
</ol>

<p>Your reasoning for choosing choice D for the first question is exactly why you should not have picked D. As you said, choice D is correct for a SUPERsaturated solution, which is not the same as a saturated solution. Choice B is correct because if temperature is constant then more solute won’t be able to dissolve in the solution, so the amount of dissolved solute will remain constant.</p>

<p>Your second question is kind of an annoying one. I think you would either have it memorized or not. I’m not sure how much any amount of logic could help you with this one. The correct answer is B.</p>

<p>E is an acid not a base! lol</p>

<p>I agree with what everyone has said so far.</p>

<p>Anyone else see #48 as an unfair problem? Both B and C are basic salts and, unless you know exactly what is in bleach, there isn’t a way to determine which is more correct.</p>

<p>I think B is a better oxidizing agent, and O is better at this than CO3.</p>