An electrolytic cell transferred 0.10 mol of electrons when a constant current of 2.0 A was applied. How many hours did this take? A. 4800h B. 80h C. 1.3h D. 0.75h E. 0.012h

38,097 results
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    The internal resistance of a dry cell increases gradually with age, even though the cell is not used. The emf, however, remains fairly constant at 1.5 V. Dry cells must be tested for age at the time of purchase by connecting an ammeter directly across the

  2. CHEMISTRY HELP !!!! CHECK !!!

    Al3+ is reduced to Al(s) at an electrode. If a current of 2.75 ampere is passed for 36 hours, what mass of aluminum is deposited at the electrode? Assume 100% current efficiency. a. 9.2 x 10–3 g b. 3.3 x 101 g c. 9.9 x 101 g d. 1.0 x 102 g e. 3.0 x 102 g

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    What makes this an oxidation-reaction? 3Ag2S+2Al(s) -> Al2S3+6 Ag(s)? Write the half-reactions showing the oxidation and reduction reactions. Identify which is the oxidation reaction and which is the reduction reason. What is oxidized in the reaction? What

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  5. Chemistry

    A current of 0.80 A was applied to an electrolytic cell containing molten CdCl2 for 2.5 hours. Calculate the mass (in grams) of cadmium metal deposited. [Enter only numbers in the blank.]

  6. Chemistry

    How many grams of copper are deposited on the cathode of an electrolytic cell if an electric current of 2.00 A is passed through a solution of CuSO4 for a period of 19.0 min?

  7. Chemistry

    Which statement correctly identifies how a lead-storage battery in a car works? A. The battery acts as a galvanic cell as it provides current to the radio. B. The battery acts as a galvanic cell as it is recharged by the alternator. C. The battery acts as

  8. Solar Energy Help ASAP

    The current density of an ideal p-n junction under illumination can be described by: J(V)=Jph−J0(eqVkT−1) where Jph is the photo-current density, J0 the saturation-current density, q the elementary charge, V the voltage, k the Boltzmann's constant, and

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  10. Chemistry

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  11. Chemistry

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    Match these with the key terms (1) A form of energy that is always transferred from a warmer substance to a cooler one. (2) device that converts hear to a small amount of electric energy often used in temperature sensors. (3) A Push button barbecue lighter

  13. Chemistry

    Elemental calcium is produced by the electrolysis of molten CaCl2. a) What mass of calcium can be produced by this process if a current of 7.5 * 10^3 A is applied for 48h? Assume that the electrolytic cell is 68% efficient. b) What is he minimum voltage

  14. Chemistry

    When hydrochloric acid (HCl) is added to water it dissociates to form H3O+ (aq) and Cl− (aq) as shown below. HCl (aq) + H2O (l) → H3O+ (aq) + Cl− (aq) What happened to the electrons in the H-Cl bond? Choose the best answer. The electrons are

  15. Chemistry --Need Help!!

    Ive posted twice, but no one's answered yet...I could really use any kind of guidance--particularly for the 1st question :) 1)) The following two half-cells are paired up in a voltaic cell. How will lowering the pH affect the ƒ´E of the overall cell?

  16. Chemistry

    A current of 2.34 A is delivered to an electrolytic cell for 85 minutes. How many grams of Au will be deposited from an aqueous solution of AuCl3?

  17. chemistry

    If a current of 5.0 Amps is passed through the electrolytic cell for .5 hour, how should you calculate the number of grams of bromine produced?

  18. chemistry

    How many minutes does it take to form 10.0L of O2 Measured at 99.8kpa and 28 C from water if a current of 1.3A passes through the electrolytic cell? what mass of h2 forms?

  19. CHEMISTRY

    The half-cell, Tl | Tl+(1 mol L-1), is connected to a Pt | H+ | H2(1 atm) half-cell in which the concentration of H+ is unknown. The measured cell voltage is 0.0841 V and the Pt | H2 | H+ half-cell is the cathode. Standard reduction potentials are given on

  20. Chemistry: Please check answers

    12. What balances charges that may build up as reduction and oxidation occur in a voltaic cell? *the salt bridge one of the half-cells the electrolyte solutions the moving electrons 13. What is the electrode in the center of the most common dry cell made

  21. ap

    The reaction 2Na+ + 2Cl− ! 2Na + Cl2 is indicative of ? cell; the sign of the anode is ? ; and ? forms at the cathode. 1. an electrolytic; negative; Na+ 2. a voltaic; positive; Na 3. an electrolytic; positive; Na 4. an electrolytic; positive; Cl2 5. a

  22. Physical Chemistry

    Three electrolytic cells containing solutions of CuNO3, Sn(NO3)2, and Fe(NO3)3, respectively, are connected in series. A current of 2.2 A is passed through the cells until 3.10 g of copper has been deposited in the cell. (a) What masses of tin and iron are

  23. physics

    An iron wire has a cross-sectional area equal to 1.20 10-5 m2. Carry out the following steps to determine the drift speed of the conduction electrons in the wire if it carries a current of 34.0 A. (a) How many kilograms are there in 1.00 mole of iron? 1

  24. chem

    Explain, in terms of electrical energy, how the operation of a voltaic cell differs from the operation of an electrolytic cell used in the Hall process. Include both the voltaic cell and the electrolytic cell in your answer. Would this be correct: In a

  25. chemistry

    Dr Bob Could you check this please? Voltaic cell---cathode is positive, accepts electrons, reduced, anode is negative, gives up electrons and is oxidized Electrolytic cell------cathode is negative, accepts electrons and is reduced. Anode is positive,

  26. chemistry

    What is the difference between a galvanic cell and an electrolytic cell? A. A galvanic cell converts reduction reactions into an electrolytic cell, and an electrolytic cell converts oxidation reactions into a galvanic cell. B. A galvanic cell converts

  27. chemistry

    An electroplating cell operates for 35 min with a current of 1,9 A. Calculate the amount, in mols, of electrons transferred.

  28. Chemistry

    How long must a constant current of 50.0 A be passed through an electrolytic cell containing aqueous Cu2+ ions to produce 3.00 moles of copper metal?

  29. Chem

    How long must a constant current of 50.0 A be passed through an electrolytic cell containing aqueous Cu2+ ions to produce 4.00 moles of copper metal?

  30. chemistry

    Examine the unbalanced electrolytic reaction. Li+(aq) + Zn(s) → Li(s) + Zn2+(aq) How many electrons are transferred in the balanced equation? 4 1 2 3

  31. Chemistry II

    For the cell Fe(s)©¦Fe2+(aq)¨UO2(g)©¦H+(aq), H2O(l)©¦Pt(s) Indicate a) standard cell potential; b) overall cell reaction c) number of electrons transferred

  32. Chemistry

    How many moles of electrons are involved in an electrolytic process if 3.07 amps are applied to the cell for 46.0 hours? The answer is 5.27, but I'm not sure how to get there. Please help!

  33. Chemistry again

    Two voltaic cells are to be joined so that one will run the other as an electrolytic cell. In the first cell, one half-cell has Au foil in 1.00M Au(NO3)3, and the other half-cell has a Cr bar in 1.00M Cr(NO3)3. In the second cell, one half-cell has a Co

  34. Electrochem

    An electrolytic cell produces aluminum from Al2O3 at the rate of ten kilograms a day. Assuming a yield of 100% a) how many moles of electrons must pass through the cell in one day? b) how many amperes are passing through the cell? c) how many moles of

  35. Physics

    When a nerve cell depolarizes, charge is transferred across the cell membrane, changing the potential difference. For a typical nerve cell, 9.0 pC of charge flows in a time of 0.50ms. What is the average current(Value and units)?

  36. Physics

    Calculate the amount of copper deposited in a zinc/Copper electrode of electrolytic cell when 2.5A of electric current is passed in 10 minutes?

  37. Inorganic chemistry

    E naught cell for the following galvanic cell is +0.254V Hg2^2(aq)+2I^-(aq) ==> 2 Hg(l) + I2(s) What is delta G naught for this reaction? Delat G naught = -nFEnaught n = the number of moles of electrons transferred between oxidizing and reducing agents as

  38. Chemistry

    Little confusing!! I need help PLZ!!! Two half cells in a galvanic cell consist of one iron (Fe(s)) electrode in a solution of iron (II) sulphate (FeSO4(aq)) and a silver (Ag(s)) electrode in a silver nitrate solution. a. Assume the cell is operating as a

  39. chemistry

    for the reaction, determine the number of transferring electrons so then i can pug into G=-nFE I'm assigning charges to each of the elements H2O2(aq) + 2ClO2(g) → O2(g) + 2HClO2(aq) (+1,-1) + (+4,-2) (0) (+1,+1,-2) since O changes from -1 to 0, so it

  40. Chemistry

    1. A student wishes to set up an electrolytic cell to plate copper onto a belt buckle. Predict the length of time it will take to plate out 2.5g of copper from a copper (II) nitrate solution using 2.5A current. At which electrode should the buckle be

  41. Chemistry

    11. Semiconductors (metalloids) have properties of both metals and nonmetals.-T? 13. Covalent bonding occurs when electrons are transferred from one atom to another.- F? 17. Bonding involves all the electrons in an atom.- T? 20. Nonpolar bonds form when

  42. chemistry

    An electrolytic cell transferred 0.10 mol of electrons when a constant current of 2.0 A was applied. How many hours did this take? A. 4800h B. 80h C. 1.3h D. 0.75h E. 0.012h

  43. Chemistry

    1)) The following two half-cells are paired up in a voltaic cell. How will lowering the pH affect the E of the overall cell? ClO3-(aq) + H2O(l) + 2e- ==> ClO2-(aq) + 2OH-(aq) Eo= 0.35 V I2(S) + 2e-==> 2I-(aq) Eo = 0.54 V A)dE will increase B)dE will

  44. chemistry

    1)) The following two half-cells are paired up in a voltaic cell. How will lowering the pH affect the E of the overall cell? ClO3-(aq) + H2O(l) + 2e- ==> ClO2-(aq) + 2OH-(aq) Eo= 0.35 V I2(S) + 2e-==> 2I-(aq) Eo = 0.54 V A)dE will increase B)dE will

  45. chemistry

    A cell, transferred 0.146 mol of electrons with a constant current of 1.24 A. How long, in hours, did this take?

  46. chemistry

    What is the correct answer? Question: An electroplating cell operates for 35 min with a current of 1.9 A. Calculate the amount, in moles, of electrons transferred. My work: Ne = It/F = 1.9A(2100 s)/9.647 x 10^4 C/mol = 3990/9.647 x 10^4 C/mol = 4136000

  47. Chemistry

    A current is passed through three electrolytic cells containing silver trixonitrate(5),coppe(2)tetraoxonitrate(6) and brine respectively.if 12.7g of copper are deposited in the second electrolytic cell.calculate(a)the mass of silver deposited in d first

  48. chemistry

    A certain voltaic cell has a standard cell voltage of 1.22 V, and 3 electrons are transferred in the overall cell reaction. What is the value of the thermodynamic equilibrium constant for this cell reaction at 298K?

  49. Chemistry

    Free-energy change, ΔG∘, is related to cell potential, E∘, by the equation ΔG∘=−nFE∘ where n is the number of moles of electrons transferred and F=96,500C/(mol e−) is the Faraday constant. When E∘ is measured in volts, ΔG∘ must be in

  50. Chemistry

    Given cell Cd | CdCl2 (0.55M) || NaBrO3 (0.34M), NaBr (0.12M), pH=1.20 | Pt 1. How many electrons are transferred? 2. What is E° for the cell? 3. What is E for the cell?

  51. Chemistry DR BOB

    Under standard conditions of 1 atm and 298.15K, the half-cell reduction potential E,zero for the anode in a voltaic cell is 0.37V. The half-cell reduction potential E,zero for the cathode of the cell is 0.67V. The number of moles, n, of electrons

  52. AP Chemistry

    This questions has 5 parts but I already have the answers for a and b. I need help on the last three parts. In an electrolytic cell, a current of 0.250 ampere is passed through a solution of a chloride of iron producing Fe(s) and Cl2(g). a) write the

  53. Chemistry

    Elemental calcium is produced by the electrolysis of molen CaCl2. What mass of calcium can be produced by this process if a current of 8500 A is applied for 39 h? Assume that the electrolytic cell is 65% efficient. I found the mass to equal 1.6 x10^5g Ca,

  54. Chemistry

    What happens to the current flow with time in an electrolytic cell ? explain. thank for helping~

  55. Physics

    If 3.25x10-3 kg of gold is deposited onto the negative electrode of an electrolytic cell in a period of 2.78 hours, what is the current through this cell in amperes? Assume that the gold ions carry one elementary unit of charge

  56. Physics

    If 3.25x10-3 kg of gold is deposited onto the negative electrode of an electrolytic cell in a period of 2.78 hours, what is the current through this cell in amperes? Assume that the gold ions carry one elementary unit of charge

  57. Physics

    If 3.25x10-3 kg of gold is deposited onto the negative electrode of an electrolytic cell in a period of 2.78 hours, what is the current through this cell in amperes? Assume that the gold ions carry one elementary unit of charge

  58. Chemistry physics

    3.25x10-3 kg of gold is deposited onto the negative electrode of an electrolytic cell in a period of 2.78 hours, what is the current through this cell in amperes? Assume that the gold ions carry one elementary unit of charge

  59. Chemistry

    Elemental calcium is produced by the electrolysis of molen CaCl2. What mass of calcium can be produced by this process if a current of 8500 A is applied for 39 h? Assume that the electrolytic cell is 65% efficient. I found the mass to equal 1.6 x10^5g Ca,

  60. chemistry(check my steps)

    The electrochemical cell described by the cell notation has a standard cell potential of -0.35 V. Calculate the Wmax (kJ) the cell has done if 1893.5 g of MnO42-(aq) (Molar Mass - 118.94 g/mol) forms. Round your answer to 3 significant figures. Pt(s) |

  61. Chemistry

    A current of 2.34 A is delivered to an electrolytic cell for 85 minutes. How many grams of Au will be deposited from an aqueous solution of AuCl3?

  62. Electrolysis

    A current of 1.2A was passed through an electrolytic cell containing dilute Tetraoxosulphate(VI) for 40minutes. Calculate the volume of gas produced at s.t.p.

  63. science

    What energy changes occur in an electrochemical cell when electric current flows from it? This is what I put down but I am not sure if it is right... In a primary cell, chemical reactions use up some of the materials in the cell as electrons flow from it.

  64. Chem -plz check work

    so i've worked on this some more, now I am asking if someone will plz check my work 2 half cells in a galvanic cell consist of one iron Fe(s) electorde in a solution of iron (II) sulphate FeSO4(aq)and a silver Ag(s) electrode in a silver nitrate solution,

  65. Chemistry

    In every electrolytic and galvanic (voltaic) cell the anode is that electrode (A) at which oxidation occurs. (B) which attracts cations. (C) at which electrons are supplied to the solution. (D) at which reduction occurs.

  66. CHEMISTRY

    The half-cell, Tl | Tl+(1 mol L-1), is connected to a Pt | H+ | H2(1 atm) half-cell in which the concentration of H+ is unknown. The measured cell voltage is 0.0841 V and the Pt | H2 | H+ half-cell is the cathode. Standard reduction potentials are given on

  67. CHEMISTRY

    The half-cell, Tl | Tl+(1 mol L-1), is connected to a Pt | H+ | H2(1 atm) half-cell in which the concentration of H+ is unknown. The measured cell voltage is 0.0841 V and the Pt | H2 | H+ half-cell is the cathode. Standard reduction potentials are given on

  68. chemistry

    How many electrons are transferred in the production of 6.06×10^−4 mol H2(g) from water?

  69. Chem

    Which of these can be deduced according to this electrochemical cell? The image is at this address: cdstools(dot)flipswitch(dot)com/asset/media/678341 A. In the cell, zinc oxidizes magnesium and causes it to lose electrons. Magnesium must be less

  70. chemistry

    How many grams of copper will be deposited at the cathode of an electrolytic cell if a current of 680.0 mA is run through a 2.5 M solution of copper sulfate for 20.0 minutes?

  71. Chemistry

    Data Electrodes: V Electrolyte: V(NO3)2 Amps: 6.0 Time (mins): 800 1. Calculate the charge in coulombs that passes through the cell during electrolysis. 2. What is the anode and cathode reaction of this cell? 3. Calculate the mass of metal deposited on the

  72. Science

    What happens when you rub an ebonite stick with a wool cloth? (Choose below) I belive the answer is B? a. Electrons are transferred to the stick, causing it to take on a negative charge. b. Electrons are transferred to the stick, causing it to take on a

  73. Chemistry

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  74. Chemistry

    Calculate the change in mass of the In electrode after the cell supplies 100 mA of current for 10 minutes. The balanced redox reaction is 2In+Cl2=2In+ + 2Cl-. I understand the idea behind the question, I just don't know if I should use 1 mol In per 1 mol

  75. Chemistiy

    Check if im right please. a. oxidation occurs at my anode ____ ** Voltaic Cell b. You can use standard reduction potential table to calculate how much voltage it takes to operate me____ **Both voltaic cell and electrolytic cell

  76. Chem

    What equation can I use to solve this kind of problem? A metal undergoes electrolytic reduction according to ne- + Mn+ ===> M. What current (in Ampères) must be provided to deposit the metal at a rate of 1.914 mol/hr if n = 3?

  77. Electricity

    suppose that you're facing a straight current carrying conductor, and the current is following toward you.the lines of magnetic force at any point in the magnetic field will act in? A)the same direction as the current. B)a clockwise direction. C)the

  78. chemistry

    Observe the diagram of the electrolytic cell (A aqueous solution of molten salt with a power supply). The molten salt is lithium flouride. Write the half reaction occuring at the cathode, following the usual style guide and making sure to balance

  79. Physics(semiconductors)

    Is electron and hole flow the same in a diode?is the following explanation correct .if not then please provide the correct one When diode is forward biased,the forward current is the sum of electron current and hole current.this current is diffusion

  80. Electrochemistry

    Hi, I'm in my final year of high school doing an electrochemistry unit and there is a concept I just don't really get. I would appreciate all helps please-- Redox reaction half reactions are: Oxidation: Zn(s) --> Zn 2+ (aq) + 2e- Reduction: Cu2+ (aq) + 2e-

  81. physics

    Drift velocity is best defined as a. the relationship between current and current density b. the number of mobile electrons per volume c. the number of mobile electrons per length d. the flux of the current density through a given area e. the average speed

  82. chemistry

    for the reaction, determine the number of transferring electrons so then i can pug into G=-nFE I'm assigning charges to each of the elements H2O2(aq) + 2ClO2(g) → O2(g) + 2HClO2(aq) (+1,-1) + (+4,-2) (0) (+1,+1,-2) since O changes from -1 to 0, so it

  83. As Physics

    Please help and do it step by step all parts of questions and use: T = time(s) I=current (amps) Q=net charge on object (Coulombs) N=no electrons (and write if added or removed from object and how) E=elementary charge Two copper wires of diameter 1 mm and 2

  84. chemistry

    Calculate the mass of Li formed by electrolysis of molten LiCl by a current of 6.7×104 A flowing for a period of 23 h . Assume the electrolytic cell is 86 % efficient. What is the energy requirement for this electrolysis per mole of Li formed if the

  85. Chemistry

    1. Distinguish between a conductor and electrolyte. 2. State Faraday's first law of electrolysis 3. What is an electrochemical cell 4. State five differences between an electrochemical cell and electrolytic cell.

  86. Chemistry

    A solution of H2SO4 was electrolyzed using the inert platinum electrodes. A) Write the balanced half-reactions for the anode and cathode in this cell. B) How many coulombs passed through the cell in 90 minutes at 8.0 amperes? C) How many moles of electrons

  87. Physics/Eletrical engineering

    Which of the following is a conducting loop in which electrons carrying electric energy may be transferred from a suitable source to do a useful work and returned to the source? a.) Direct current b.) Indirect current c.) Electric circuit d.) source of

  88. Chemistry

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  89. Physics

    In a computer monitor, an electron beam with a current of 4x10^-6 A is directed at the screen. How many electrons are transferred to the monitor in 2 minutes.

  90. Please help with really hard chem question?

    An electrolysis experiment was run for 17.5 minutes at an average current of 191 milliamps (mA). The mass lost by the copper anode was 0.0679 grams. a) Calculate the number of coloumbs transferred. (coloumb=ampsxsec) b) Calculate the moles of copper lost

  91. ET3034TUx Solar Energy

    The current density of an ideal p-n junction under illumination can be described by: J(V)=Jph−J0(eqVkT−1) where Jph is the photo-current density, J0 the saturation-current density, q the elementary charge, V the voltage, k the Boltzmann's constant, and

  92. NEED HELP! CHEMISTRY

    Three electrolytic cells containing solutions of CuNO3, Sn(NO3)2, and Fe(NO3)3, respectively, are connected in series. A current of 2.2 A is passed through the cells until 3.10 g of copper has been deposited in the cell. (a) What masses of tin and iron are

  93. Chemistry

    A student wishes to set up an electrolytic cell to plate copper onto a belt buckle. Predict the length of time it will take to plate out 2.5g of copper from a copper (II) nitrate solution using a 2.5-A current. At which electrode should the buckle be

  94. Chemistry

    Consider a cell at 255 K: line notation Pb-Pb2+(1.27M)--Fe3+(2.29M)-Fe Given the standard reduction potentials calculate the cell potential after the reaction operated long enough for Fe3+ to have changed by 1.432M? I know that Fe3+ is the cathode which

  95. Chemistry

    Consider a cell at 255 K: line notation Pb-Pb2+(1.27M)--Fe3+(2.29M)-Fe Given the standard reduction potentials calculate the cell potential after the reaction operated long enough for Fe3+ to have changed by 1.432M? I know that Fe3+ is the cathode which

  96. Chemistry

    Consider a cell at 255 K: line notation Pb-Pb2+(1.27M)--Fe3+(2.29M)-Fe Given the standard reduction potentials calculate the cell potential after the reaction operated long enough for Fe3+ to have changed by 1.432M? I know that Fe3+ is the cathode which

  97. Chemistry

    Consider a cell at 255 K: line notation Pb-Pb2+(1.27M)--Fe3+(2.29M)-Fe Given the standard reduction potentials calculate the cell potential after the reaction operated long enough for Fe3+ to have changed by 1.432M? I know that Fe3+ is the cathode which

  98. Chemistry/Electrochem

    Consider a cell at 255 K: line notation Pb-Pb2+(1.27M)--Fe3+(2.29M)-Fe Given the standard reduction potentials calculate the cell potential after the reaction operated long enough for Fe3+ to have changed by 1.432M? I know that Fe3+ is the cathode which

  99. Chemistry

    Consider a cell at 255 K: line notation Pb-Pb2+(1.27M)--Fe3+(2.29M)-Fe Given the standard reduction potentials calculate the cell potential after the reaction operated long enough for Fe3+ to have changed by 1.432M? I know that Fe3+ is the cathode which

  100. college chemistry

    The voltaic cell described by the balanced chemical reaction has a standard emf of 4.05 V. Calculate the equilibrium constant (Kc) for the reaction at 25 oC. Round your answer to 3 significant figures. F2(g) + Mn(s) → 2F-(aq) + Mn2+(aq) Mn2+/Mn -1.18

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