Chem 1B

Spring 2008

Practice Exam 1--Selected Answers

2.

C₂H₂O₂Br^-

C₅H₅NH⁺

PO₄^3-

4. 

a)  2 H⁺ + C₂O₄^2- → H₂C₂O₄

b)  2 HF + Ba²⁺ + 2 OH^- → 2 H₂O + BaF₂

 

5.  pH = 11.4₈

6.  Acetonitrile has a polar end and a non-polar end.  This works with either a polar or non-polar solvent.

7.

dipole-dipole

dipole-induced dipole

8.

No, Q>K, rxn will go to left  (Q = 0.70)

9. 

P_CO2 = 0.0387 atm

P_NH3 = 0.0774 atm

10. 

1.  same as

2.  same as

3.  greater than

4.  Flask A.  In flask B, [H₂O] is less, so the rate H₂O_(l) → H₂O _(g)  is less than for pure water, and you get less vapor.

EC.  A will boil, T will stay the same, balloon will inflate.  B will not boil, T will increase.

11. 

a)  pH = - log [H⁺]

b)  forward and reverse rate are the same (or no change on macroscopic scale)

    continuous change on nanoscale

   closed system

d)  proton acceptor