I believe I know the answer to #4
ANSWER: Two moles to a first approximation
*Disclaimer* I'm pretty sure I'm right, but I could be wrong
Mn metal can be used as a sacrificial electrode to prevent the rusting of an iron pipe. So, the correct option is (c) Mn.
Commonly, sacrificial electrodes are employed to stop another metal from corroding or oxidising. A metal that is more reactive than the metal being shielded must serve as the sacrificial electrode. Magnesium, aluminium, and zinc are the three metals most frequently used in sacrificial anodes.
Manganese-Magnesium (Mn-Mg) electrode is more suited for on-shore pipelines where the electrolyte (soil or water) resistivity is higher since it has the highest negative electropotential of the three. In order to replenish any electrons that could have been lost during the oxidation of the shielded metal, the highly active metal offers its electrons.
Therefore, Mn metal can be used as a sacrificial electrode to prevent the rusting of an iron pipe. So, the correct option is (c) Mn.
Learn more about electrode here:
brainly.com/question/17060277
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Answer:
a. Change of state
Explanation:
Because you will see that the state has changed
According to provided equation it is clear that Zn metal is oxidized from Zn⁰ into Zn²⁺ which means that Zn metal dissolves and forming Zn²⁺ solution so the correct answer is:
mass of the Zn(s) electrode decreases
