Question I- Answer as required.

(A) Use the given equation to complete the following table and predict which the thermodynamic process could be spontaneous or nonspontaneous.(10 pts)

ΔG^o = ΔH^o - TΔS^o

ΔH^o	ΔS^o	- TΔS^o	ΔG^o	Comments (Spontaneous Or Non Spontaneous)	Condition of T
-Ve	+Ve	...........	-Ve		N/A
+Ve	..........	+Ve	+Ve		N/A
-Ve	..........	+Ve	-Ve		.......................
-Ve	-Ve	+Ve	+Ve		.......................
+Ve	+Ve	.........	+Ve		.....................
+Ve	+Ve	.........	-Ve		......................

4 pt (B) Explain Why?

1- Given that ΔG = ΔH - TΔS And ΔH= ΔE + W” And ΔS = q ÷ T, also

q= ΔE + W₁ explain the meaning of ΔG.

2- Using the formula S = k ln W (Boltzmann equation)

to show how the entropy of impure substance at 0.0 K is not zero.

6 pts (C) Explain the meaning of the following:

1- ªG^o is zero:

2- n(reaction order) is zero:

3- ªH^o is an inadequate criterion of spontaneity:

Question II- Consider the given exothermic reaction and the accompanying data when answering the following questions.

2 H_2(g) + 2 NO _(g) ======= N_{2 (g)} + 2 H₂O (K_c = 90 at727 ^oC.)

2 pt a) Write the K_c expression for this reaction.

2 pt b) What is the value of K_p at 727 ^oC.?

4 pt c) Use Le Chatelier's principle to predict the effect of the following on the position of the above reaction equilibrium. ( compare Q and K in each case)

1- Addition of some N_2(g).

2- Removal of some NO _(g).

3- Cooling the reaction container and it's contents.

4- Decreasing the pressure.

4 pt d) For the above reaction, if >G^o 727^oC is -32.509 KJ, what will be the value of K_p .

6 pt e) Suppose the following mechanism is correct for the above reaction.

step 1 2 NO ==== N₂O₂ fast

step 2 N₂O₂ + H₂ ===== N₂O + H₂O slow

step 3 N₂O + H₂ ===== N₂ + H₂O fast

Write the reaction rate (law) equation.

2 pt f) What is the overall order of the above reaction?

Question I11-Choose the correct answer(s):

1- For the reaction N₂ + 3H₂ ====== 2NH₃ ,the relationship between K_p and K_c is given by:

a) K_p = K_cx(RT)^-2 b) K_c = K_px(RT)^-2 c) K_p = K_c x (RT)² d) K_c = K_px(RT) e) None

2- For the first order reaction which it's rate constant is equal to 10^-3 year^-1 at 25 ^oC , the half life time is,

a) 0.35 Yr. b) 693 year c) 0.457 year d) 8.316x10³ month e) 12300 hour.

3- Which of the following is/are correct about the catalytic reactions?

a) They are zero order b) Homogeneous c) Exothermic

d) Nonspontaneous e) Decreases the activation energy of the reactions

4- When Δ G^o is negative, this means that:

a) K = 1 b) K > 1 c) T = 0 d) S = 0 e) None

5- For the reaction 2AX _(s) + BY_(l) ------ A₂B_(l) + XB_(g) .which of the following statement/s is/are correct:

a) This reaction is heterogeneous b) K_c = P_C

c) second order d) Unimolecular e) Bimolecular

6- In part (5), Which of the following is/are correct:

a) It is one step reaction mechanism b)Δ S_(prod)> ΔS_(react)

c) It is multi-step reaction mechanism d) Δ V is positive.

7- A substances that formed in one elementary step of a multi-step mechanism and consumed in another is known to be:

a) Reactant b) Product c) Intermediate d) Activated complex e) Transition state.

8- The process which happen under constant pressure is known to be :

a) Isothermic b) Adiabatic c) Isolated d) Isobaric e) Isochoric.

9- In the formula k = A e^-Ea/RT symbol A is known as :

a) Rate b) Order c) Frequency factor d) Activation energy e) Enthalpy.

10- The system which exchange both energy and matter with the surroundings is known to be:

a) Isothermal b) Spontaneous c) Open d) Isolated e) Closed.

Question VI-Consider the given exothermic reaction when answering the following question:

CH₃CHO(l) + Cl₂(g) ====== CH₃COCl(g) + HCl(g)

Obeys the following rate law, rate = k [Cl₂]^1/2[CH₃CHO]

The following series of steps is proposed for this reaction mechanism.

Step 1 Cl₂ ========= 2 Cl.

Step 2 H. + Cl₂ ========= HCl + Cl.

Step 3 CH₃CHO + Cl. ========= CH₃COCl + H.

3 pt a) Write K_p and K_c expression for the above reaction.

1 pt b) What is the overall reaction order?

2 pt c) What is/are the intermediate/s in the mechanism?

2 pt d) Write the t_0.5 - k relationship for this reaction.

5 pt e) which of the steps above is the rate determining step?

3 pt f) What is the sign of ΔH, ΔS, ΔG

2 pt g) Label fast steps.

2 pt h) If the rate of this reaction decreases when temperature increases, propose an explanation for such behavior.

Question VII- Answer as required:

10 pt A) List five important facts that work as a bases of qualitative analysis. Give example that illustrates each fact: (10 pts)

10 pt B) Sketch a separation scheme for the mixture of Cu²⁺, Fe³⁺, Al³⁺ ,Ni²⁺ and Mg²⁺,

Using the following reagents: HCl, H₂S, NH₄Cl, NH₄OH and NaOH. (10 pts)

Question VIII- Explain why: ( 4 pt each )

1- Formation of two salts of H₂CO₃ such as NaHCO₃, and Na₂CO₃, while H₂SO₄ doesn’t

2- NH₄⁺ is stronger acid than Na⁺.

3- The mixture of equi 0.2M solution of sodium acetate and acetic acid has higher buffer capacity than the mixture of equi 0.5M NaCl and HCl.

4- The pH of aqueous KCl solution is 7.

5-Addition of NH₄ Cl(Cl^-,NH₄⁺) to a solution of NH₄OH (NH₄⁺, OH^-) will suppress its ionization.

Question IX:

10 pts A) Given that K_sp of Pb(OH)₂ is 1.2X10^-15, and the following dissociation :

Pb(OH)₂ W Pb²⁺ + 2OH^-

Calculate :

1- The concentration of Pb ions in pure water.

2- The pH value of the suspension of Pb(OH)₂ in water.

3- The concentration of Pb ions in a solution of pH= 10.

10 pts B) Identify the fact/s that can be used to explain the following separation:

1- Fe(OH)₃/Pb(OH)₂ + excess NaOH ====> Pb(OH)₃⁺ (aq) + Bi(OH)_{3 (PPT)}

2- Cr³⁺ / Ni²⁺ + excess NH₄OH ===> Ni[NH₃]₄²⁺ + Cr(OH)₃(ppt).

3- Ni²⁺/ Cu²⁺ + ( HCl + H₂S) ====> CuS(ppt) + Ni²⁺

4- Al³⁺/Ba²⁺ + (NH₄Cl/NH₄OH) ====> Al(OH)₃(ppt) + Ba²⁺

Question X-

Question XI - Consider the given exothermic reaction and the accompanying data when answering the following questions:

CO_(g) + Cl_2(g) ========= COCl_2(g) K_c = 4.57x10⁹ at 100 ^oC.

2 pt a) Write the K_c expression for this reaction.

2 pt b) What is the value of K_p at 100 ^oC.?

4 pt c) Use Le Chatelier's principle to predict the effect of the following on the position of the above reaction equilibrium.

1- Removal of some Cl_2(g).

2- Removal of some COCl_2(g).

3- Cooling the reaction container and it's contents.

4- Decreasing the pressure.

2 pt d) Calculate >G^o for this reaction at 100^oC.

2 pt e) For the above reaction, if >G^o 200^oC is -109.48 KJ, what will be the value of K_p .

6 pt f) Suppose the following mechanism is correct for the above reaction.

step 1 Cl₂ ==== 2 Cl. fast

step 2 Cl. + CO ===== COCl fast

step 3 COCl + Cl₂ ===== COCl₂ + Cl. slow

step 4 2Cl. ===== Cl₂ fast

Write the reaction rate (law) equation.

2 pt g) What is the overall order of the above reaction?

Question XII- Solve the following problems, ( 5 pt each )

1- Balance the following equation, and identify the pH range required for this reaction.

I₂ + NO₃^- = NO₂(g) + IO₃^-

2- If the half life of ²¹⁴Pb is 26.77 minutes, calculate the disintegration rate for ²¹⁴Pb .

3- Use the standard electrode potentials to calculate the ΔG^o for the following reaction,

Al_{(s) +} Fe²⁺_(aq) ------< Al³⁺ + Fe_(s)

is this reaction spontaneous?

4- Calculate the nuclear binding energy of ²⁷₁₃Al^{3+ nucleus}, given that mass is ²⁷₁₃Al³⁺ 26.98 amu.

Question XIII-Choose the correct answer(s):

1- For the reaction N₂ + 3H₂ ====== 2NH₃ ,the relationship between K_p and K_c is given by:

a) K_p = K_cx(RT)^-2 b) K_c = K_px(RT)^-2 c) K_p = K_c x (RT)² d) K_c = K_px(RT) e) None

2- For the first order reaction which it's rate constant is equal to 10^-3 year^-1 at 25 ^oC , the half life time is,

a) 0.35 Yr. b) 693 year c) 0.457 year d) 8.316x10³ month e) 12300 hour.

3- Which of the following is/are correct about the catalytic reactions?

a) They are zero order b) Homogeneous c) Exothermic

d) Nonspontaneous e) Decreases the activation energy of the reactions

4- When Δ G^o is negative, this means that:

a) K = 1 b) K > 1 c) T = 0 d) S = 0 e) None

5- For the reaction 2AX _(s) + BY_(l) ------ A₂B_(l) + XB_(g) .which of the following statement/s is/are correct:

a) This reaction is heterogeneous b) K_c = P_C

c) second order d) Unimolecular e) Bimolecular

6- In part (5), which of the following is/are correct?

a) It is one step reaction mechanism b)Δ S_(prod)> ΔS_(react)

c) It is multi-step reaction mechanism d) Δ V is positive.

7- Substances that formed in one elementary step of a multi-step mechanism and consumed in another is known to be:

a) Reactant b) Product c) Intermediate d) Activated complex e) Transition state.

8- The process which happen under constant pressure is known to be:

a) Isothermic b) Adiabatic c) Isolated d) Isobaric e) Isochoric.

9- In the formula k = A e^-Ea/RT symbol A is known as :

a) Rate b) Order c) Frequency factor d) Activation energy e) Enthalpy.

10- The system which exchange both energy and matter with the surroundings is known to be:

a) Isothermal b) Spontaneous c) Open d) Isolated e) Closed.

Question XIV: Explain why:

1- In the following cell

Ag/Ag⁺ 2 Cd/ Cd ²⁺ Ag electrode may lose weight.

2- The nuclear reaction :

P( proton) ===> n (neutron ) + ₊e (Positron) Is endoergic _,While

P( proton) + e (K-shell) ====> n Is exoergic.

3- K metal cannot be generated from the aqueous electrolytes.

4- Hydrolysis of aqueous HBr, produces H₂ gas at the cathode and Br₂ gas at the anode, while that of aqueous HF produces H ₂ gas at the cathode, and O₂ gas at the anode.

Question XV- Write the major difference/s between: (4 pt each)

1- Natural radioactivity and nuclear transmutation.

2- Galvanic (Voltaic) cell Electrolytic cell

3- Mechanical (paints) and cathodic protection from corrosion.

4- Positron emission and K- electron capture.

5- Electrolysis of aqueous solution of NaCl and aqueous CuCl₂.

Question XVI - Answer each of the following with true or false. If a statement is false correct it.

----- 1- E^o for the cell CdCd²⁺  Ni²⁺ Ni, is positive.

----- 2- For conversion of proton to neutron , it is easier through k electron capture rather than positron emission.

----- 3- A car battery during charging process is an example of Galvanic (Voltaic) cell.

----- 4- A mass change of 1gram in nuclear reaction is equivalent to 934.31 Mev.

----- 5- Nuclei of odd numbers of protons and even numbers neutrons are generally more stable than those which have even numbers of protons and even numbers of neutrons.

----- 6-The following is a notation for Electrolytic cell:

AgAg⁺Zn²⁺Zn.

----- 7- Both Al and Cu metals can be produced by electrolysis of their aqueous solutions.

----- 8- The amount of radiation that deposits 1x10^-2 J of energy per Kg of tissue, is the definition of rem.

----- 9- Nucleus that has more than 230 nucleons adjust n/p ratio by emitting β particles.

----- 10- The radioactive decay of ²³⁸₉₂ U to Pb is considered to be second order reaction.

Question XVII- Choose the correct answer/s: ( 2 pt each )

1- Each of the following is weaker than HCl except:

a) H₂CO₃ b) HClO₂ c) HBr. d) HClO₃ e)HI

2- Each of the following has a common ion with NaHSO₃ except

a)NaHSO₄ b) Na₂SO₃ c) H₂SO₃ d) CaS₂O₃ e) H₂SO₄.

3- Aqueous solutions of NH₄Cl is:

a) Acidic b) Alkaline c) Neutral d) Basic e) None

4- For alcoholic solution of 10^-3 M HCl, the pOH is:

a) 12 b) 10.56 c) 11 d) -log K_a e) none.

5- Which of the following is a conjugate base of HPO₄ 2- ^?

a) PO₄^3- b) H₃PO₄ c) H₂PO₄^- d) H₃PO₃ e)H₂PO₃^-

6- " The amount of acid/ base a buffer can neutralize before the pH begins to change appreciably" is the definition of:

a) Strong acid b) Amphoteric substances c) Lewis base

d) Buffer solutions e) Buffer capacity

7- Acid strength is determined by:

a) Acid decomposition b) Acid stability c) k_a d) #of H⁺/molecule e) Acid origin.

8- Precipitation occurs when:

a) K_sp= 10^-14 b) K_sp < Q (ionic product) c) Q < K_sp d) K_sp = Q e) Q = 10^-14

9- Metal hydroxides/oxides which dissolve in strongly acidic or strongly basic media are known to be:

a) Salts b) Amphoteric c) Strong acids d) Weak bases e) polyprotic acids

10- Which of the following is a Lewis base?

a) HCl b) BCl₃ c) CO₃^2- d) NH₃ e) H₃O⁺

Question XVIII- What is/are the difference/s between: (5 pt each )

1- Electrochemical series and Spectrochemical series.

2- High spin complex and low spin complex.

3- H₂NCH₂CH₂NH₂ and CN^- as a ligand.

4- Alkene and Alkyne.

5- Tetrahedral and Octahedral complexes.

Question XIX- A) Write the structural formula for each of the following: (3 pt each)

a) 2,2 Dimethyl-,6,6 Dibromo 3- Heptyne.

b) cis 2,3 Dichloro 2-Pentene.

c) Hexammine Chromium(III) Nitrate.

d) Sodium Tetrabromo (ethylenediamine) Cobaltate(III).

e) 2-Amino 3,4 di-methyl Hex -3-ene.

B- Choose the correct answer(s) :(10 pt )

1- In each of the following, the value of Δ is higher than spin pairing energy except:

a) Fe(CN)₆^3- b) NiCl₄^2- c) Cr(CN)₆^3- d) CoF₆^3- e) Mn(CN)₆ ^4-.

2- The oxidation number of Chromium in [Cr(NH₃)₄Cl₂]Cl is:

a) -3 b) 6 c) 2 d) -2 e) None

3- Which of the following complexes has coordination number of 6.

a) [Zn(NH₃)₂Cl₂] b) K₃[Fe(CN)₆] c) [Cu(NH₃)₄]²⁺ d) [Co(NH₃)₅Cl]²⁺

e)Pt(NH₃)₂Cl₂.

4- Complexes which have higher number of unpaired electrons are known to be:

a) Inert b) paramagnetic c) diamagnetic d) low spin e) high spin.

5- The functional group/s in NO₂-CH₂=CH-CH₂ -CO-CH₂CH₂OH is/ are:

a) Nitrile, Ketone, Ether and Aldehyde.

b) Nitro , Alkene, Ether and Aldehyde.

c) Nitro, Alkene , Ketone and Alcohol.

d) Alcohol, Alkene , Ether and Nitro.

e) Amino , Alcohol, Alkyne and Ketone.

Question XX- A) Write the major difference/s between:( 2.5 pt each)

1- Cathodes in galvanic or voltaic cell and Cathodes in electrolytic cell.

2- Positron emission and K- electron capture.

B) Choose the correct answer/s: ( 2 pt each )

1- Each of the following is weaker than HCl except :

a) H2CO3 b) HClO2 c) Hbr. d) HClO3 e)HI

2- Each of the following has a common ion with NaHSO3 except

a)NaHSO4 b) Na2SO3 c) H2SO3 d) CaS2O3 e) H2SO4.

3- Aqueous solutions of NH4Cl is:

a) Acidic b) Alkaline c) Neutral d) Basic e) None

4- For alcoholic solution of 10-3 M HCl, the pOH is:

a) 12 b) 10.56 c) 11 d) -log Ka e) none.

5- Which of the following is a conjugate base of HPO4 2- ?

a) PO43- b) H3PO4 c) H2PO4- d) H3PO3 e)H2PO3-

6- " The amount of acid/ base a buffer can neutralize before the pH begins to change appreciably" is the definition of:

a) Strong acid b) Amphoteric substances c) Lewis base

d) Buffer solutions e) Buffer capacity

7- Acid strength is determined by:

a) Acid decomposition b) Acid stability c) ka d) #of H+/molecule e) Acid origin.

8- Precipitation occurs when:

a) Ksp= 10-14 b) Ksp < Q (ionic product) c) Q < Ksp d) Ksp = Q

e) Q = 10-14

9- Metal hydroxides/oxides which dissolve in strongly acidic or strongly basic media are known to be:

a) Salts b) Amphoteric c) Strong acids d) Weak bases e) polyprotic acids

10- Which of the following is a Lewis base?

a) HCl b) BCl3 c) CO32- d) NH3 e) H3O+