An oxide of copper was reduced to form copper metal by reaction with hydrogen. Use the data in the table to find the empirical formula of this oxide of copper. Table reads as follows: Container – 25.61g, container+copper oxide (before reaction) – 26.97g, container+copper (after reaction) – 26.82g.

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The empirical formula of any compound can be found using the steps attached in the link shared. To begin with, we need to find the masses of Cu and O from the data given.

We have:

Container + Copper oxide = 26.97 g

Container = 25.61 g

So, the mass...

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The empirical formula of any compound can be found using the steps attached in the link shared. To begin with, we need to find the masses of Cu and O from the data given.

We have:

Container + Copper oxide = 26.97 g

Container = 25.61 g

So, the mass of copper oxide = 26.97 - 25.61 = 1.36g

Container + Copper = 26.82 g

So, the mass of copper = 26.82 - 25.61 = 1.21 g

The mass of oxygen = Copper oxide - Copper = 1.36 - 1.21 = 0.15 g

The empirical formula can be figured using the following process, which is shown using sodium (Na) and oxygen (O) as examples:

  1. Mass of Na = 1.857 g, and mass of O = 0.645 g
  2. Molar mass of Na = 23 `g mol^-1`, and molar mass of O = 15.99 `g mol ^-1`
  3. Moles of Na = `1.857/23 = 0.0807`mol and moles of O = `0.645/15.99 = 0.04033`mol
  4. Divide both by the smallest mole: `0.0807/0.04033 = 2` and `0.04033/0.04033 = 1`
  5. Ratio of Na : O = 2 : 1
  6. Hence, the empirical formula: Na2O

Follow the steps above, using the molar masses of copper and oxygen, to find your compound’s empirical formula.

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