+ 0.76 + 0.34 = 1.0 Volts
maurice.mutuku answered the question on October 31, 2019 at 08:33
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The standard hydrogen electrode is used as the reference electrode. Some of the difficulties in using hydrogen gas as an electrode are:
- Hydrogen is a gas at 25oC
- Hydrogen does not conduct electricity
-The half-cell reaction,
is slow and takes long to reach equilibrium.
Explain how these difficulties are solved in the standard hydrogen electrode
Date posted: October 31, 2019. Answers (1)
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(i) Give a reason why these substances react and yet both are oxides
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Date posted: October 31, 2019. Answers (1)
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Date posted: October 31, 2019. Answers (1)
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Date posted: October 31, 2019. Answers (1)
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(Molar gas volume at s.t.p = 22.4dm3,...(Solved)
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Date posted: October 31, 2019. Answers (1)
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Date posted: October 31, 2019. Answers (1)
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Copper (II) sulphate solution was electrolysed using copper electrode. A Current of 0.5A was
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a) Which electrode decreased in mass during electrolysis? Explain
b) Calculate the quantity of charge needed to deposits 1 mole of copper
Date posted: October 31, 2019. Answers (1)
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Date posted: October 31, 2019. Answers (1)
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Give a reason for your answer.(Solved)
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Date posted: October 31, 2019. Answers (1)
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c) Study the cell represented below;
i) Identify the electrodes
ii) Write equations for the reaction taking place in each half- cell
iii) Determine the cell equation and the electromotive force (e.m.f) of the cell represented in
(c) above
iv) In which direction does the electrons flow in the external circuit of the cell whose e.m.f
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d) A steady current of 2.5A was passed for 15 minutes through a cell containing divalent ions
M2+. During this process 0.74g of metal M was deposited (IF = 96500C)
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Date posted: October 31, 2019. Answers (1)
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The reaction is carried out in presence of platinium-rhodium catalyst at 1173k and a pressure of 911.952k pa.
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a) Reduction in pressure
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Date posted: October 31, 2019. Answers (1)
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-Cathode
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Date posted: October 31, 2019. Answers (1)
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(i) Given the standard electrode potential of Zinc is -0.76V and that of copper is +0.34V, suggest;
(i)The identity of W
(ii) The identity of X
(iii) The equation for the overall cell reaction
(iv) The reading on the voltmeter
Date posted: October 31, 2019. Answers (1)
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Date posted: October 31, 2019. Answers (1)
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(iii) The electrolysis involved passing an electric current of 4A for one hour. Calculate the mass of
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Date posted: October 31, 2019. Answers (1)
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(a) State the observations made at the end of the experiment
(b) Give a reason for the observations made in (a) above
(c) Calculate the e.m.f of the cell above
Date posted: October 31, 2019. Answers (1)
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(i) Identify the electrode which is ;
(a) The least reducing agent
(b) The strongest oxidizing agent
(ii) Calculate the e.m.f of the cell formed when the two electrodes are connected
(iii) Write a cell representative for the cell above
Date posted: October 31, 2019. Answers (1)
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ammonia (Ammonium hydroxide)until in excess
(ii) What conclusion can be drawn from Step IV only? Explain
(iii) What observation would indicate the presence of a NO3- ion in step I?
(iv) Write the formula of the anion in residue V. Explain
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Date posted: October 29, 2019. Answers (1)
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(a) Identify the substances represented by the letters
(b) Give equations for the reactions in which:-
(i) Substance B is formed from the solution of A on electrolysis
(ii) Substance B is formed from solution A when reacted with E
(c) Give one use of gas C
(d) Name the ion responsible for the deep blue solution
Date posted: October 29, 2019. Answers (1)