A mass of a copper oxide weighed 10.00grams. The reaction was run and the amount of just copper obtained was 8.88grams. What is the empirical formula of the compound?

10 g = copper oxide

8.88 = g Cu
-------
1.12 = g oxygen

mols Cu = 8.88/atomic mass Cu
mols O = 1.12/atomic mass O
Find the ratio of the atoms to each other. I think you will find it to be Cu2O.

To determine the empirical formula of a compound, the first step is to calculate the number of moles of each element present.

Given:
Mass of copper oxide = 10.00 grams
Mass of copper obtained = 8.88 grams

To calculate the number of moles, we need the molar mass of copper (Cu) and the molar mass of oxygen (O).

The molar mass of copper (Cu) is 63.55 g/mol.
The molar mass of oxygen (O) is 16.00 g/mol.

Step 1: Calculate the number of moles of copper (Cu):
Number of moles of copper (Cu) = Mass of copper obtained / Molar mass of copper (Cu)
Number of moles of copper (Cu) = 8.88 g / 63.55 g/mol

Step 2: Calculate the number of moles of oxygen (O):
Number of moles of oxygen (O) = (Mass of copper oxide - Mass of copper obtained) / Molar mass of oxygen (O)
Number of moles of oxygen (O) = (10.00 g - 8.88 g) / 16.00 g/mol

Step 3: Determine the mole ratio between copper (Cu) and oxygen (O):
Divide the number of moles of each element by the smallest number of moles obtained.

For copper (Cu), we obtained 0.1396 moles.
For oxygen (O), we obtained 0.0575 moles.

Dividing both values by 0.0575 (the smaller value), we get approximately:
Copper (Cu): 2.42
Oxygen (O): 1.00

This gives us a ratio of approximately Cu2O.

Therefore, the empirical formula of the compound is Cu2O, which represents copper(I) oxide.