Copper metal of 1.23 g sample is reacted completely with chlorine gas to produce 2.61 g of copper chloride. Determine the empirical formula of the compound?

The empirical formula of the compound is

Explanation:

Mass of Copper (Cu) = 1.23 g

Mass of Chlorine (Cl)  = Mass of copper chloride - mass of copper = (2.61 - 1.23) g = 1.38 g

Step 1 : convert given masses into moles

Moles of Cu =

Moles of Cl =

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For Cu =

For Cl =

The ratio of Cu : Cl = 1 : 2

Hence the empirical formula is

c is the answer because when something is left after something evaporates that shows the chemical change.