<p>Oh, yes, you’re right. I misread the question and mentally associated the “foil” with electroplating.</p>
<p>Blue book:</p>
<ol>
<li><p>The question itself tells you that NaNO3 and Pb(NO3)2 are soluble, and it also tells you that they are white solids. A double displacement reaction cannot occur because there would simply be an exchange of nitrate ions, and nothing would actually happen. Here, you are forced to assume that a white solid will dissolve to give a white (colourless) solution. Thus, there will be no precipitate, and no colour to the solution. E is the answer.</p></li>
<li><p>Electrolytes are essentially ions. In order to answer this question, you need to know that all ammonium compounds are highly soluble (I don’t know if you’ve ever worked with ammonium chloride, but it literally dissolves instantly). As such, they dissociate into the polyatomic ions that composed them. Of the answer choices, only choice C will create ions, and thus electrolytes, in solution.</p></li>
<li><p>Kw=[H+][OH-]. This is the equation for the autoionization of water, and the constant Kw is equal to 10^-14. This means that in neutral water, the concentrations of H+ and OH- will both be equal to 10^-7, which is due to the normal autoionization of water. </p></li>
</ol>
<p>In the first equation, a strong monoprotic acid is mixed with a strong monoprotic base, both in equal concentrations. As such, they will give a neutral solution, one in which the concentration in hydroxide ions will be 10^-7: answer choice C.</p>
<ol>
<li><p>The only substance from the answer choices that is a base is choice B. As such, it will have the highest pH.</p></li>
<li><p>0.1M NaOH is a very high concentration. If you were to calculate the pH of a solution with that concentration of sodium hydroxide, you would find that it would be exactly 13. This eliminates choice B. Choices A and D are acids, which necessarily have a pH under 7. We have already determined that choice C is neutral, which eliminates it. The only option left is E.</p></li>
<li><p>This question tests your knowledge of colligative properties. You should be able to deduce that sucrose is an organic molecules, and organic molecules often don’t dissociate in water. As such, a 1M sucrose solution will have a 1M concentration in particles, whereas a 1M NaCl solution will have a 2M concentration in particles (NaCl fully dissociates in water). Thus, the NaCl will have a higher concentration of particles in solution, and hence a lower freezing point. The first statement is false.</p></li>
</ol>
<p>With this explanation, you can also deduce that the second statement is also false.</p>
<ol>
<li>In order to answer this question, you need to memorize the common strong acids. You should know that acetic acid is a weak acid, and that hydrochloric acid is a strong acid. Thus, hydrochloric will fully dissociate in water, and acetic acid won’t; acetic acid will have a smaller [H+]. The first statement is true.</li>
</ol>
<p>The second statement is true. The formula of acetic acid is CH3COOH, whereas the formula of hydrochloric acid is HCl. I think that is enough of an explanation.</p>
<p>The second statement has nothing to do with the reason why one solution will have a greater hydrogen ion concentration than the other. As such, the answer is T,T, and not T,T, CE.</p>
<ol>
<li><p>A saturated hydrocarbon is one in which each carbon atom is attached to four other atoms, which may only be either carbon or hydrogen, and nothing else. For instance, C2H6 is a saturated hydrocarbon, because each carbon atom is attached to three hydrogen atoms, and to the other carbon. However, C2H4 is not a saturated hydrocarbon, because the carbon atoms are attached by a double bond; each carbon atom only has three groups surrounding it. The general formula for a saturated hydrocarbon is CnH2n+2. Choice A obeys this general formula, and is thus a saturated hydrocarbon. (Note that cyclic hydrocarbons, if they are cycloalkanes and not cycloakenes or cycloalkynes, are also saturated, but do not obey to the above formula.)</p></li>
<li><p>Ca(OH)2 + H2SO4 –> CaSO4 + H2O. You can balance it yourself.</p></li>
<li><p>In order to answer this question, you need to know that the boiling point of a given liquid is attained when its vapor pressure reaches or surpasses that of the atmospheric pressure. The question tells you that the atmospheric pressure on Pikes Peak is 455 mm Hg, and, using the data table you are given, you will notice that 455 mm Hg is between 350 mm Hg and 538 mm Hg, which correspond to temperatures of 60C and 70C, respectively. As such, choice C is correct.</p></li>
<li><p>This is a question that is based on descriptive chemistry, and thus the answer is something you could know only if you had memorized common household compounds and their uses.</p></li>
<li><p>This is a particularly tricky question. </p></li>
</ol>
<p>Initial conditions:
V= 25.3 mL
P= The atmospheric pressure and the vapor pressure are opposed in direction, and two opposing vectors counteract one another. As such, the pressure is 749.8 mm Hg - 19.8 mm Hg. Don’t bother attempting to convert this to kPa because you don’t have a calculator.</p>
<p>The temperature remains constant, and is thus not a necessary aspect of the calculations.</p>
<p>Now, you should recall Boyle’s gas law, which may be expressed as:</p>
<p>P1<em>V1 = P2</em>V2</p>
<p>You know that P2 is equal to 1 atm, and you should be aware that 1 atm is equal to 760 mm Hg. Now, your pressure is expressed in the same units, and all that’s left is to calculate the final volume, the volume under a pressure of 760 mm Hg</p>
<p>P1V1 = P2V2
(749.8 mm Hg - 19.8 mm Hg)(25.2 mL) = (760 mm Hg)V2
V2 = ((749.8 mm Hg - 19.8 mm Hg)(25.2 mL))/760 mm Hg</p>
<p>Hope that helps.</p>