<p>1.) This exothermic reaction is catalyzed by MnO2(s):</p>
<p>2H2O2(aq) ---> 2H2O(l) + O2(g)</p>
<p>Which of the following will increase the rate of this reaction?
I. Raising the temperature
II. Increasing the surface area of MnO2</p>
<p>A. 1 only
B. 2 only
C. 1 and 2
D. neither 1 nor 2</p>
<p>Isn’t it:</p>
<p>Reactants —> Products + Heat
(it is exothermic)</p>
<p>So if you add more heat (increase temperature), then the concentration of Reactants will go up, because of Le Chatlier’s Principle. But what does that have to do with the rate?</p>
<p>Also, II will obviously increase the rate of the reaction (more SA, faster reaction).</p>
<ol>
<li>A student is asked to prepare a buffer solution with a pH of 4.00. This can be accomplished by using a solution containing which of the following?</li>
</ol>
<p>Ka: HNO2 = 4.5 </p>
<p>Bump!!?!??!?!</p>
<p>Bump!?!!?!?!??! Come on guys!</p>
<p>I believe 1 is C. Temperature, without a doubt, increases rate. More collisions. Now, as for surface area, I would expect more surface area to mean a higher chance of collision and thus a higher rate. Google search would probably answer this.</p>
<h1>2 dunno. Covering acid-base next month haha.</h1>
<p>does anyone know number 2?</p>
<p>No one can do #2?</p>
<p>Bump!! ! ! ! !</p>
<p>
</p>
<p>help!! ! Pleaaaaasee</p>
<p>it would be c cause a buffer first of all needs a weak acid and the salt of that weak acid and for acid/base the ph is close to the exponent</p>
<p>I understand for a buffer you need a weak base + weak acid. And also you need a pKa near the pH. So therefore you would need HNO2, but why do you also need its salt?</p>
<p>come on people!!!</p>