Chemical Formula of Copper Oxide

What is the formula of the copper oxide?

Based on the given data, what will be the chemical formula of the copper oxide formed?

Answer:

The formula of the copper oxide would be Cu2O.

When a 7.298 g sample of copper reacts completely with oxygen, forming a copper oxide with a final mass of 8.217 g, the formula of the copper oxide is determined based on the mass and mole ratios of copper and oxygen.

The mass of copper sample is 7.298 g, and the mass of oxygen can be calculated by subtracting the mass of copper sample from the final mass of the copper oxide:

Mass of oxygen = 8.217 g - 7.298 g = 0.919 g

Using the mole ratios of copper and oxygen, we can find that:

Number of moles of Cu = 7.298 g / 63.546 g/mol = 0.115 mol

Number of moles of O = 0.919 g / 16 g/mol = 0.057 mol

Dividing the moles of Cu and O by the smaller value (0.057 mol), we get the mole ratios to be:

Cu = 0.115 mol / 0.057 mol = 2

O = 0.057 mol / 0.057 mol = 1

Therefore, the formula for the copper oxide formed is Cu2O, where there are 2 moles of copper for every 1 mole of oxygen.

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