ملتقى الفيزيائيين العرب

Problem1:calculate the ph of each of the following solution:

(A)0.0010 M HCl

(B)0.76 M KOH

Problem2:calculate the hydrogen ion concentration in mol ⁄ L for solutions with the following pH values:

(A)2.42

(B)11.21

(C)6.96

(D)15.00

Problem3:How much NaOH (in grams) is needed to prepare 546 mL of solution with a pH of10.00 ?

Problem4:calculate the pH of 1.00 L of the buffer 1.00 M CH3COONa ⁄ 1.00 M CH3COOH before and the addition of :

(A)0.080 mol NaOH

(B)0.12 mol HCl

Assumethat there is no change in volume.

Problem5: A solution mad eby mixing 5.00 × 102 mL of 0.167 MNaOH with 5.00 × 102 mL of 0.100 M CH3COOH. Calculate theequilibrium concentrations of H+, CH3COOH, CH3COO-,OH- and Na +

Problem 6: Balance the following redoxequations using half reaction method:

(A) H2O2 + Fe2+Fe3+ + H2O

(B) Cu- + HNO3Cu2++NO + H2O

( C ) CN- + MnO4-CNO-+MnO2

(D) Br2BrO3 - +Br-

(E) S2O32-+ I2I-+ S4O62-

Problem 7: predict whether the following reaction would occurspontaneously in aqueous solution at 25 C. Assume that the initialconcentrations of dissolved species are all 1.0 M

(A) Mg (s) + Pb2+(aq) Mg2+(aq) + Pb(s)

(B) Br2 (I) + 2I- (aq) 2Br-(aq) +I2(s)

(C ) O2(g) + 4H+(aq)+4Fe2+ (aq) 2H2O(I) + 4Fe3+(aq)

(D) 2Al(s) +3I2(s) 2Al3+(aq) +6I- (aq)

Problem 8: which spcies in each pairis a better reducing agent under standard state conditions?

(A)Na or Li

(B) H2 or l2

(C ) Fe2+ or Ag

(D) Br- or Co2+

http://i.imgur.com/QR5UtxL.png