An electrical engineer is analyzing an electroplating run and wants to calculate the charge that has been used. She knows that the cell voltage is 0.25 V and that 10.3 kWh was expended. What was the charge? If the current of the apparatus is 3.0 A, how long was it running?

A certain half-reaction has a standard reduction potential Eed=+0.45 V. An engineer proposes using this half-reaction at the anode of a galvanic cell that must provide at least 1.40 V of electrical power. The cell will operate under standard conditions. Note for advanced students: assume the engineer requires this half-reaction to happen at the anode of the cell. olo Is there a minimum standard reduction potential that the half-reaction used at the cathode of this cell can have? yes, there is a minimum. E red Ov Ar If so, check the "yes" box and calculate the minimum. Round your answer to 2 decimal places. If there is no lower limit, check the "no" box. no minimum Is there a maximum standard reduction potential that the half-reaction used at the cathode of this cell can have? E = Ov yes, there is a maximum. red If so, check the "yes" box and calculate the maximum. Round your answer to 2 decimal places. If there is no upper limit, check the "no" box. no maximum

What mass of aluminum metal can be produced per hour in the electrolysis of a molten aluminum salt by a current of 26 A ? Express your answer using two significant figures.

A certain metal M forms a soluble sulfate salt MSO4. Suppose the left half cell of a galvanic cell apparatus is filled with a 200. mM solution of MSO4 and the right half cell with a 4.00 M solution of the same substance. Electrodes made of M are dipped into both solutions and a voltmeter is connected between them. The temperature of the apparatus is held constant at 20.0 °C. Which electrode will be positive? What voltage will the voltmeter show? Assume its positive lead is connected to the positive electrode. Be sure your answer has a unit symbol, if necessary, and round it to 2 significant digits. 0 left right x10 X S

A certain metal M2(SO4)3 forms a soluble sulfate salt . Suppose the left half cell of a galvanic cell apparatus is filled with a 1.00 M solution of M2(SO4)3 and the right half cell with a 1.00 mM solution of the same substance. Electrodes made of M are dipped into both solutions and a voltmeter is connected between them. The temperature of the apparatus is held constant at 35.0 C. What voltage will the voltmeter show?

Thomas Edison invented an electric meter that was nothing more than a simple coulometer, a device to measure the amount of electricity passing through a circuit. In this meter, a small, fixed fraction of the total current supplied to a household was passed through an electrolytic cell, plating out zinc at the cathode. Each month the cathode could then be removed and weighed to determine the amount of electricity used. If 0.25% of a household’s electricity passed through such a coulometer and the cathodeincreased in mass by 1.83 g in a month, how many coulombs of electricity were used during that month?

A certain metal M forms a soluble nitrate salt MNO3. Suppose the left half cell of a galvanic cell apparatus is filled with a 175. mM solution of MNO3 and the right half cell with a 3.50 M solution of the same substance. Electrodes made of M are dipped into both solutions and a voltmeter is connected between them. The temperature of the apparatus is held constant at 35.0 °C. Which electrode will be positive? What voltage will the voltmeter show? Assume its positive lead is connected to the positive electrode. 0 Be sure your answer has a unit symbol, if necessary, and round it to 2 significant digits. left right ■ □x10 X S

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41.  What mass of gold is produced when 16.8 AA of current are passed through a gold solution for 10.0 minmin ? Express your answer with the appropriate units.

What mass of aluminum metal can be produced per hour in the electrolysis of a molten aluminum salt by a current of 30 A ? Express your answer using two significant figures.