2.2. The mole and the Avogadro constant
A subsection of Chemistry, 9701, through 2. Atoms, molecules and stoichiometry
Listing 4 of 4 questions
The apparatus shows a cell which can be used to determine a value of the Avogadro constant, L. X power supply silver electrodes electrolyte Y variable resistor Name component X. Suggest a suitable electrolyte Y. In an experiment, a current of 0.200 A was passed through the cell for 40.0minutes. The mass of the silver cathode increased by 0.500 g. The charge on the electron is –1.60×10–19 C. Calculate the: ● ● number of moles of silver deposited on the cathode ● ● number of coulombs of charge passed ● ● number of electrons passed ● ● number of electrons needed to deposit 1 mol of silver at the cathode.  
9701_m18_qp_42
THEORY
2018
Paper 4, Variant 2
View
A student decided to determine the value of the Faraday constant by an electrolysis experiment. The following incomplete diagram shows the apparatus that was used. Apart from connecting wires, what two additional pieces of equipment are needed for this experiment? Complete the diagram, showing additional equipment connected in the circuit, and showing the powerpack connected to the correct electrodes. List the measurements the student would need to make in order to use the results to calculate a value for the Faraday constant. Using an equation, state the relationship between the Faraday constant, F, the Avogadro constant, L, and the charge on the electron, e. The value the student obtained was: 1 Faraday = 9.63 × 104 Coulombs Use this value and your equation in to calculate the Avogadro constant (take the charge on the electron to be 1.60 × 10–19 Coulombs) hydrogen being collected power pack inert electrodes – + dilute H2SO4
9701_s05_qp_4
THEORY
2005
Paper 4, Variant 0
View
Complete Table5.1 to predict the substance liberated at each electrode during electrolysis of the indicated electrolyte with inert electrodes. Table 5.1 electrolyte substance liberated at the anode substance liberated at the cathode PbBr2concentrated NaCl Cu(NO3)2 An electrolytic cell is set up to determine a value for the Avogadro constant, L. The electrolyte is dilute sulfuricacid and both electrodes are copper. When a current of 0.600 A is passed through the acid for 30.0minutes, the anode decreases in mass by 0.350 g. State the relationship between the Faraday constant, F, and the Avogadro constant, L. Use the experimental information in and data from the table on page23 to calculate a value for the Avogadro constant, L. Show all working.  Avogadro constant, L = 
9701_s22_qp_42
THEORY
2022
Paper 4, Variant 2
View
Questions Discovered
4