During the discharge of an alkaline battery, 4.50 g of Zn is consumed at the anode of the battery. (a) What mass of MnO₂ is reduced at the cathode during this discharge?

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Hey everyone in this example, we're considering an alkaline battery with 2.63 g of zinc. We need to calculate the mass of zinc hydroxide formed, assuming that all the zinc metal undergoes oxidation using manganese for oxide. So we're going to make note of our molar mass Of an atom of zinc on our periodic tables and we would see that it has a molar mass equal to a value of 65.38 graham's Permal. Also referring to our molar mass of zinc hydroxide. We're gonna see according to our periodic tables that we have a molar mass of .42 g per mole. We also want to make note of the ratio of zinc in our zinc hydroxide And we would see that we just have one atom of zinc in zinc hydroxide. So we're going to say we have a 1-1 molar ratio and we're going to make note of this ratio as a conversion factor later on. But right now we want to go ahead and find the mass of our zinc hydroxide. And so we're gonna start out with what we're given from the prompt which is 2. g of just sink. And we're gonna multiply this by our molar mass as a conversion factor, which we noted above. So we said above that for that we have 65.38g of zinc for one mole of zinc according to our periodic tables. And so now we're able to cancel out grams of zinc. We're at moles of zinc and now we're going to move into our multiple ratio where we stated, we have one more of zinc in one more of zinc hydroxide. So this allows us to cancel out moles of zinc. Now we're at moles of zinc hydroxide and now we're going to plug in our last conversion factor where we noted according to our periodic tables that we have for one mole of zinc hydroxide, Its molar mass equal to 99.42 g of zinc hydroxide. And so now we're able to cancel out moles of zinc hydroxide and we're left with our final unit being our mass. And what we're going to get here is a value equal to about 3.99 g of zinc hydroxide. And so this would be our final answer here to complete this example as our molar mass of zinc or rather as our mass of zinc hydroxide that is formed, assuming that all the zinc metal undergoes oxidation using our manganese for oxide. So what's highlighted in yellow is our final answer? I hope that everything was clear. But if you have any questions, please leave them down below and I will see everyone in the next practice video

During the discharge of an alkaline battery, 4.50 g of Zn is consumed at the anode of the battery. (a) What mass of MnO₂ is reduced at the cathode during this discharge?

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Key Concepts

Redox Reactions

Stoichiometry

Molar Mass

During the discharge of an alkaline battery, 4.50 g of Zn is consumed at the anode of the battery. (a) What mass of MnO2 is reduced at the cathode during this discharge?

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Verified Solution

Key Concepts

Redox Reactions

Stoichiometry

Molar Mass

During the discharge of an alkaline battery, 4.50 g of Zn is consumed at the anode of the battery. (a) What mass of MnO₂ is reduced at the cathode during this discharge?