M6 Exam

Write a balanced chemical equation for the reac- tion of bromine and triolein, a triglyceride of oleic acid, CH3(CH2),CH=CH(CH,),COOH. 2.

Question 6 ii)

2.2 6. (1) Define pH in words. The strong acid HClag has a pH value of 1, use the following equation for a strong acid: Claa HClaa Hog + and convert the following expression to deduce the hydrogen ion concentration: pH = -log10 [H+] (ii) Use the above expression to deduce the pH of HCl (ag) given the concentration of the acid to be 4.5 mol/dm³ pH =

Write the expression Kc for the following reactions. (a) Fe2+(aq) + Ce4+(aq) ⇋ Fe3+(aq) + Ce3+(aq) (b) CaCO3(s) ⇋ CaO(s) + CO3(g)

When ammonium sulfate dissolves, both the anion and cation have acid-base reaction: (NH4)2SO4(s) 2NH4* + SO42- NH4* + NH3(aq) + H* SO2- + H2O → HSO4 + OH Ksp = 276 Ka = 5.70 x10-10 Кь 3 9.80 х 10-13 (a) (b) (c) Write a charge balance for this system. Write a mass balance for this system. Find the concentration of NH3(aq) if the pH is fixed at 9.25.

Fill in the Blanks Type your answers in all of the blanks and submit When sulfurous acid, H2SO4 is dissolved in water it undergoes stepwise dissociation, initially giving up its first proton the in the reaction: H2SO3(aq) + H20(aq) = H30 (aq) + HSO, (aq) The resulting HSO, (aq) species is amphoteric in solution and can thus react with water as either an acid or as a base. The equilibrium expressions below show these 2 scenarios. Identify whether HSO, (aq) behaves as an acid or as a base in these reactions. HSO (aq) + H20(1) = H,SO3(aq) + OH (aq) In this reaction HSO, acts as a/an Type your answer here HSO (aq) + H2O(1) = So, (aq) + H;0 (aq) In this reaction HSO, acts as a/an Type your answer here

Chemists working with fluorine and its compounds some- times find it helpful to think in terms of acid-base reac- tions in which the fluoride ion (F¯) is donated and ассеpted. (a) Would the acid in this system be the fluoride donor or fluoride acceptor? (b) Identify the acid and base in each of these reactions: CIF;O2 + BF; CIF,O, · BF, -- TiF, + 2 KF – K2[TiF,]

(a) Ionic Solids do not dissolve in non-polar solvents. (TRUE OR FALSE) (b) H3AsO4 is a weak acid. (TRUE OR FALSE) (c) Once a chemical reaction has come to equilibrium, the reaction comes to a complete halt.(TRUE OR FALSE)

What is the total ionic reaction and net ionic reaction of  Na2CO3 (aq)+ 2HCl(aq) -> 2NaCl (aq)+ CO2(g) +  H2O(l)?

7. (a) for which of the following compounds is it hazardous to breathe dust/ vapor/ fumes: acetylsalicylic acid, salicylic acid, acetic anhydride, acetic acid, phosphoric acid? (b) based on the boiling point or melting point of the compounds, which are you most likely to inhale accidentally? (d) of all these chemicals, which is most important to handle in a fume hood?

State whether each of the following statements is true orfalse. Justify your answer in each case.(a) Sulfuric acid is a monoprotic acid.(b) HCl is a weak acid.(c) Methanol is a base.

In the following acid-base titration experiment NaOH(aq) + HNO3(aq) ———> NaNO3(aq) + H2O(1). What is the molarity of the HNO3 solution if 18.3 mL of 0.115 M NaOH was used to neutralize 25 mL of HNO3? (a) 0.157 M (b) 0.0842 M (c) 3.978 M (d) 0.0157 M

The pH reading of a sample of each substance is given. Calculate the hydrogen ion concentration of the substance. (Give your answers in scientific notation, correct to one decimal place.) (a) Beer: pH = 5.3 [H+] =  × 10 M (b) Water: pH = 6.8 [H+] =  × 10 M

Give the answers that should be filled in the blanks below: Acetic acid solution: pH = 5.80; (a) [H+] =         M; (b) [OH-] =          M Ammonia solution: [H+] = 5.90 x 10-9 M; (c) pH =           ; (d) pOH =

In the following acid-base titration experiment CH3COOH (aq) + NaOH (aq) ———-> CH3COONa (aq) + H2O (l). What is the molarity of the NaOH solution if 11.6 mL of 3.0 M acetic acid is required to neutralize the sodium hydroxide in 25.00 mL of NaOH solution? (a) 0.65 M (b) 6.5 M (c) 96.6 M (d) 1.392 M

How could you distinguish NH4Cl and AgCL?  (a) By smell (b) By color (c) By solubility in water (d) By taste

2 CoCl2(aq) + 8 NH3(aq) + H2O2(aq) + 2 NH4Cl(aq)  2 [Co(NH3)5Cl]Cl2(s) + 2 H2O(l) In a 50-mL Erlenmeyer flask, cobalt(II) chloride hexahydrate (1.075 g), an aqueous solution of ammonia (1.2 mL, 15 M), ammonium chloride (0.505 g), and hydrogen peroxide (1.0 mL, 30.0% (w/w), density = 1.10 g/mL) were combined. After completion of the reaction, [Co(NH3)5Cl]Cl2 (0.450 g) was isolated. What was the percent yield of the product?

Part A)  Place the following elements in order of increasing atomic radii: Mg, Na, Rb, Cl.     Part B)   Balance the following oxidation-reduction reaction:                                                  NH3(g) +    O2(g)     =>     NO(g) +     H2O(g) The sum of all the stoichiometric coefficients in the balanced equation is:                  (a)   4             (b)   7              (c)   10             (d)   19                             (e)  None of those, if so what is your answer   Part C)  A freighter carrying a cargo of uranium hexafluoride sank in the English Channel in late August 1984. Uranium hexafluoride was contained in 30 drums, each having a volume of 1.62×106 L. Uranium hexafluoride density is 5.09 g/mL. What was the mass (in ton, 1 ton=1000 kg) of sunk UF6? a)  47×105         b)   9.43×107          c)  2.47374×105             d)   0.247(e)   None of those. If so, what is your answer?

= (1) H H H H (2) (3)

Which of the following equations represents the correct reaction between calcium metal and water?           (A) 2Ca(s)  +  2H2O(l)  -->  2CaOH(aq)  +  H2(g)          (B) Ca(s)  +  2H2O(l)  -->  Ca(OH)2(aq)  +  H2(g)          (C) Ca(s)  +  H2O(l)  -->  CaO(s)  +  H2(g)          (D) None of the above

2. Which of the following solutions has a pH = 15? (A) A solution cannot have a pH = 15. (B) 1.0 x 10-15 M NaOH (C) 10.0 M NaOH (D) 15 M NaOH (E) 1.0 M NaOH

A sample of calcium nitrate crystal hydrate with its mass of 1.1808 g was heated at 150oC resulting in its mass being reduced to a constant value of 0.8204 g of anhydrous salt. What is the mole ratio of water to anhydrous salt in this salt hydrate. (A)    2                   (B)    4               (C)    6                (D)   7              (E)    None of those, if so, what is your answer?

Because the oxide ion is basic, metal oxides react readily with acids.(a) Write the net ionic equation for the following reaction:FeO1s2 + 2 HClO41aq2¡Fe1ClO4221aq2 + H2O1l2(b) Based on the equation in part (a), write the net ionicequation for the reaction that occurs between NiO(s) and anaqueous solution of nitric acid.

When a solution of sodium hydroxide is added to a solution of ammonium carbonate, H,O is formed and ammonia gas, NH, is released when the solution is heated. Write a net ionic equation for this reaction. Both NaOH and (NH ),CO, exist as dissociated ions in aqueous solution.

100 mL of 0.1 M NaOH solution was poured into 20 mL of 0.2 M H2SO4 solution and mixed well.  What was the final pH of the mixture? (a)   pH =1.00               (b) pH= 1.08              (c)pH=12.0               (d)pH=1.80             (e)pH = 12.2

Write a balanced net ionic equation for each of the following acid–base reactions.   HCl(aq)+KOH(aq)→KCl(aq)+H2O(l)HCl(aq)+KOH(aq)→KCl(aq)+H2O(l) Express your answer as a net ionic equation. Identify all of the phases in your answer.

Indicate whether each of the following statements is trueor false:(a) If something is oxidized, it is formally losing electrons.(b) For the reaction Fe3+(aq) + Co2+(aq)----->Fe2+(aq) +Co3+(aq), Fe3+(aq) is the reducing agent and Co2+(aq)is the oxidizing agent.(c) If there are no changes in the oxidation state of the reactantsor products of a particular reaction, that reactionis not a redox reaction.

1. a) Write the formula for the conjugate base of HPO4^-2  b) Write the formula for the conjugate acid of NH3