Can You Pass This Electrolysis Quiz?

A cathode is negatively charged, which means it has an excess of electrons. Since opposite charges attract, the cathode will attract positively charged ions, also known as cations.

Graphite can conduct electricity because it has 4 free electrons, but only 3 are used for bonding. This means that there is 1 free electron available for conducting electricity.

When the voltage of the battery increases, the current also increases. According to Ohm's Law, the current is directly proportional to the voltage. Therefore, if the voltage increases, the current will also increase. Electrolysis is a process that requires the flow of electric current, so if the current increases, the rate of electrolysis will also increase, not decrease. Hence, the given statement is false.

In order for electrolysis to occur, the electrolyte must be molten or aqueous. This is because in a molten or aqueous state, the electrostatic forces of attraction between the ions in the electrolyte are overcome, allowing the ions to become mobile. This mobility of ions is necessary for the flow of electric current during electrolysis.

Pure water is not a good electrolyte because water molecules are held together by covalent bonds, which means they do not dissociate into ions. In order for a substance to be a good electrolyte, it needs to have mobile ions or electrons that can carry an electric current. Since pure water does not have these mobile ions or electrons, it cannot conduct electricity effectively.

In electrolysis, a DC current should be used because it ensures that the charges of the electrodes remain constant. This is important because it allows the components involved in the electrolysis process to stay at their respective electrodes. If the charges were not constant, the components could migrate and mix, leading to an inaccurate or ineffective electrolysis process. Therefore, using a DC current helps to maintain the stability and integrity of the components during electrolysis.

In the purification of copper ore, the impure copper should be used as the anode. This is because during the electrolysis process, the anode is the electrode where oxidation occurs. By using the impure copper as the anode, it will lose electrons and be oxidized, forming copper ions. These copper ions will then travel to the pure copper cathode, where reduction occurs, allowing the impurities to be removed and leaving behind pure copper.

When electrolysis is carried out with concentrated sulfuric acid as the electrolyte and inert electrodes, hydrogen ions (H+) and sulfate ions (SO4^2-) will be discharged at the electrodes. This is because sulfuric acid dissociates into hydrogen ions and sulfate ions in solution. At the cathode (negative electrode), hydrogen ions will be reduced to form hydrogen gas (H2), while at the anode (positive electrode), sulfate ions will be oxidized to form oxygen gas (O2) and water (H2O).

During the electrolysis of molten NaOH using inert electrodes, the observation at the positive electrode (anode) will be the effervescence of a colorless, odorless gas. This gas is oxygen (O2) which is produced by the oxidation of water molecules at the anode. At the negative electrode (cathode), there will be deposits of a silvery-gray solid. This solid is sodium (Na) which is formed by the reduction of sodium ions (Na+) present in the molten NaOH.

The correct answer is Pb²⁺ (l) + 2e⁻ → Pb (l). This equation represents the reduction reaction that occurs at the cathode during the electrolysis of molten lead (II) iodide. In this reaction, lead ions (Pb²⁺) gain two electrons (2e⁻) to form lead atoms (Pb). This reduction reaction is necessary to balance the oxidation reaction that occurs at the anode during the electrolysis process.