25. The method detection limit is
(A) The lowest concentration of the calibration curve
(B) The minimal detectable signal intensity of an analyte
(C) The lowest detectable concentration of an analyte
(D) The minimal measurable concentration of an analyte
(E) The minimum concentration of an analyte that can be reliably distinguished from the blank

21. Place the following in order of decreasing radius. (A)Te2- ＞F- ＞O2- (B) Te2- ＞ O2-＞ F-(C) O2-＞F-＞Te2- (D) F- ＞ Te2- ＞ O2- (E)F- ＞O2- ＞Te2-

22. Commercial grade hydrofluoric acid (HF = 20.01 g mol-1) solutions are typically 48.0% (w/w). What is the molality of the HF, if the solution has a density of 1.15 g mL-1? (A) 20.9 m (B) 27.6 m (C) 40.1 m (D) 46.1 m (E) 53.1 m

23. Among the following, which radical is the most stable?(A) I (B) II (C)III (D)IV (E)V

24. Place the following in order of decreasing magnitude of lattice energy.NaF MgO CsI AIN (A) CsI ＞ AIN ＞ MgO ＞ NaF (B) AIN ＞ MgO ＞ NaF ＞ CsI (C) NaF ＞ CsI ＞ MgO ＞ AIN (D) AIN ＞ MgO ＞ CsI ＞ NaF (E) CsI ＞ NaF ＞ MgO ＞ AIN

26. What is the rate law for the given reaction and its mechanism? (A) Rate = k[HgCl2][C2O42-] (B) Rate = k[HgCl2]2[C2O42-] (C) Rate = k[Hg2Cl2] (D) Rate = k[HgCl2][C2O42-]2 (E) Rate = k[HgCl2]2[C2O42-]2

27.Which one has a different relationship between the signal and concentration? (A) Scattering (B) Fluorescence (C) Phosphorescence (D) Absorption (E) Emission

28.A 50.0-mL aliquot of 1.0 M NaBrO (HBrO: pXa = 8.70) is titrated with 1.0 M HCl. What is the pH after adding 25.0 mL of the acid? (A) 11.30 (B) 9.30 (C) 8.70 (D) 5.30 (E) 3.30

29.Which option below outlines an effective method for relocating the position of a π bond? (A) Substitution, followed by addition (B) Addition, followed by substitution (C) Elimination, followed by addition (D) Addition, followed by elimination (E) None of the above

30. The nitrosonium ion, NO+, forms numerous fascinating complexes with nickel, cobalt, and iron. Based on molecular orbital theory, which of the following statements accurately describes NO+? (A) The nitrosonium ion, NO+, possesses a bond order of 2 and exhibits paramagnetism (B) The nitrosonium ion, NO+, possesses a bond order of 2 and exhibits diamagnetism (C) The nitrosonium ion, NO+, possesses a bond order of 3 and exhibits paramagnetism (D) The nitrosonium ion, NO+, possesses a bond order of 3 and exhibits diamagnetism (E) None of these choices are correct

31. At pH 8.0, the predominant form of ethylenediaminetetraacetic acid (EDTA; H4Y: K1= 1.02 x 10-2, K2 = 2.14 x 10-3, K3 = 6.92 x 10-7, K4 = 5.50 x 10-11) is (A) H3Y- (B)H2Y2- (C) HY3- (D) Equal amounts of H2Y2- and HY3- (E)Y4-