A mass of 37.5 grams of mercury oxide is decomposed by heating. The reaction is 2HgO > 2Hg + O2. A. How many moles of mercury oxide is decomposed? B. How many moles of oxygen are prepared? C. How many grams of oxygen are prepared?

1 answer

2HgO ==> 2Hg + O2
mols HgO = grams HgO/molar mass HgO = ?
Then from the equation you get 2 mols Hg for every 2 mols HgO initially so mols Hg =- mols HgO.

mols O2 will be 1/2 mols HgO.

grams O2 = mols O2 x molar mass O2 = ?

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