2 AP Chem Multiple Choice that confuse me

Test Preparation AP Test Preparation
1

<p>here are two MC im confused on.. can anyone help me out? We did this stuff so long ago.. ahhh Thanks!</p>

<p>(1) One of the most important factors in determining the solublity of a solute in a solvent it
A) melting point of solute
B) boiling point of solute
C) intermolecular forces of solute + solvent
D) molar mass of solute
E) molar mass of solvent</p>

<p>and..</p>

<p>(2) The ammonium ion can act as a weak acid because it can react with water to form
A) ammonia and hydroxide ions
B) ammonia and hydrogen ions
C) ammonia and hydrogen atoms
D) hydrogen and hydroxide ions
E) none of the above
Thanks again :)</p>

2

<h1>1) C. Like dissolves like, and the forces determine whether or not it is even possible for a solute to dissolve in a solvent. For instance, CH4 will have a hard time dissolving in water because it is nonpolar, but KCl will dissolve more readily because it is polar (ionic).</h1>

<h1>2) NH4+ + (H2O) --> H+ + NH3</h1>

<p>I believe the answer is B, but I'm not so sure on this one. Since you can't add more H+ or OH to the ammonium ion, the H2O serves to hydrolyze the ion.</p>

3

<p>2 is B. shanianwang gave the right explanation</p>

4

<p>yep both of those are correct</p>