<p>Test tomorrow! Please, please help if you can!!! I'm going craaaaazzzyyyyy!</p>
<p>1) What is the effect of temperature on entropy?</p>
<p>At first, I was clear on temperature increasing and entropy increasing because there is more disorder. BUT, if the temperature is increasing, there are more collisions happening, and if the product being formed happens to be a solid forming from a liquid, then doesn't entropy decrease?</p>
<p>2) What are the unique properties of water concerning pressure and melting/boiling points? How does high pressure of water cause lower MP and BP, and low pressure of water cause high MP and BP?</p>
<p>3) If given a chemical equation to balance, how do you know whether to balance it the redox way? (Like some equations the oxidation states change, but you can still balance it the simple way without dealing with electrons...like H2 + O2 --> H2O.. I think there is a better example that I'll try finding).</p>
<p>4) Which does NOT react with dilute H2SO4?
A) NaNO3
B) Na2S
C) Na3PO4
D) Na2CO3
E) NaOH</p>
<p>A is the answer..WHY WHY WHY?</p>
<p>5) <strong>MOST IMPORTANT QUESTION PLEASE!</strong> Why is the cathode negative in electrolytic cells but positive in galvanic cells? And why is the anode positive in electrolytic cells and negative in galvanic cells? And how do you know whether zinc is the anode or cathode or copper is the anode or cathode? Like I was asked what the anode was, and I was stuck between two choices: A) Zn --> Zn2+ + 2e- and B) Cu --> Cu2+ + 2e-</p>
<p>6) Pressure inside a closed system = pressure outside of a closed system when water boils? Why?</p>
<p>Are delta H and delta S related? Like proportional? (If reaction is exothermic, entropy increases or anything?)</p>
<p>Is a solution at equilibrium ALWAYS saturated?</p>
<p>Ca(OH)2 and Ba(OH)2 strong bases?</p>
<p>This is a true statement: When the pressure drops sufficiently, the water starts to boil</p>
<p>Why does decreasing atmospheric pressure on a pot of boiling water cause it to boil vigorously?</p>
<p>Correcting pressure over water and when levels dont equals!! (I understand you have to subtract the water vapor pressure but I dont get it when the levels dont equal).</p>
<p>A true statement said that vapor pressure is independent of external pressures? But isnt that not truebecause like if the system is closed or open will also determine the vapor pressure and that is an external force, no?</p>
<p>eh, what's easy for you probably isn't so easy for me :( but thanks anyway
And since you already took the test, it makes me wonder if College Board gives the same version of the test given across the world.
What country do you live in (if you dont mind me asking)?</p>
<p>4) I'm not sure, but I think: NO3 would just be a spectator ion and not have an effect on the reaction, whereas the others will lead to the formation of precipitate.
I don't know if that logic is right, as it isn't even completely clear to me.</p>
<p>2) Think of it this way: High pressure on water forces it to be in much closer contact = more inter-molecular bonds/forces = harder to evaporate because it is harder to break the H-bonds. On the other hand, low pressure makes it easier to break the H-bonds and therefore easier to evaporate.</p>
<p>delta g (gibbs free energy) = delta h - (t)(delta s)</p>
<p>i dont know if you knew that, but thats how the two are related.</p>
<p>delta s is positive (entropy is random) when delta h is negative (heat released)
heat being released (and not obsorbed) is favorable and spontaneous, thus delta s is positive</p>