To make a chemical cell, two metal electrodes are dipped in a salt or dilute acid solution and joined by a wire. What causes the electrical current?The flow of electrons from the more reactive metal to the less reactive metalThe formation of metal ions in the salt solutionThe flow of electrons from the less reactive metal to the more reactive metalThe loss of heat to the surroundings

Simple chemical cells involve two electrodes. Which of the following statements is correct?Both electrodes must be carbonThe electrodes must be two different metalsOne electrode must be carbonThe electrodes must be the same metal2To make a chemical cell, two metal electrodes are dipped in a salt or dilute acid solution and joined by a wire. What causes the electrical current?The flow of electrons from the more reactive metal to the less reactive metalThe formation of metal ions in the salt solutionThe flow of electrons from the less reactive metal to the more reactive metalThe loss of heat to the surroundings3A zinc/carbon chemical cell (or battery) contains a paste of ammonium chloride. What is the function of this paste?To hold the electrodes in placeTo hold the wire in placeTo act as an electrolyteTo act as an electrode4What is the balanced equation of the overall reaction that takes place in a fuel cell?H2 + O2 → H2O2H2O → 2H2 + O22H2 + O → 2H2O2H2 + O2 → 2H2O5Which of the following is a disadvantage of using hydrogen as a fuel?Hydrogen gas is highly flammableFuel cells can be a range of sizesThe only waste product is waterFuel cells do not require recharging6Which of the following statements about hydrogen-oxygen fuel cells is not true?The only waste product is waterAn acidic electrolyte is requiredHydrogen must be supplied constantlyElectrical energy is produced from the oxidation of hydrogen

What allows electrons to flow between electrodes in an electrochemical cell?A.Salt bridgeB.Electrolyte solutionsC.Conducting wireD.Battery

Which of the following is not a function of salt bridge in an electrochemical cell ?To maintain electrical neutrality of the solutionTo complete the circuit so that current can flowTo supply ions to cathodic and anodic compartmentTo increase cell voltage

In an electrochemical cell:

When an electric current passes through a pure metallic conductor, whether solid or liquid.(1) There is chemical effect of electric current.(2) There is change in colour.(3) There is no chemical effect of electric current.(4) Both (1) & (2