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What mass of MnO2 is produced when 445 grams of H2O are reacted?

H20 + 2MnO4+ Br- + BrO3 + 2MnO2 + 20H-

User Bristol
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Answer:

when 445 grams of H2O are reacted, 4,300 grams (or 4.3 kilograms) of MnO2 are produced.

Step-by-step explanation:

The balanced chemical equation for the reaction is:

16H+ (aq) + 2MnO4- (aq) + 10Br- (aq) → 2MnO2 (s) + 5Br2 (aq) + 8H2O (l)

According to the equation, 2 moles of MnO4- react to produce 2 moles of MnO2. Therefore, we need to find out the number of moles of MnO4- that react with the given amount of H2O and then use stoichiometry to calculate the number of moles of MnO2 produced.

First, let's calculate the number of moles of H2O:

mass of H2O = 445 g

molar mass of H2O = 18.015 g/mol

number of moles of H2O = mass/molar mass = 445 g/18.015 g/mol = 24.7 mol

From the balanced equation, we can see that 1 mole of H2O reacts with 2 moles of MnO4-. Therefore, the number of moles of MnO4- required to react with 24.7 mol of H2O is:

number of moles of MnO4- = 2 × number of moles of H2O = 49.4 mol

Since 2 moles of MnO4- produce 2 moles of MnO2, we can say that 1 mole of MnO4- produces 1 mole of MnO2. Therefore, the number of moles of MnO2 produced is also 49.4 mol.

Finally, we can calculate the mass of MnO2 produced:

mass of MnO2 = number of moles of MnO2 × molar mass of MnO2

mass of MnO2 = 49.4 mol × 86.94 g/mol = 4,300 g

Therefore, when 445 grams of H2O are reacted, 4,300 grams (or 4.3 kilograms) of MnO2 are produced.

User Marcelo Machado
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