Question #3015d

1 Answer
Nov 11, 2015

Cu2O

Explanation:

First, we need to find the amount in moles of each substance. WE have the mass for each so we use the formula:

n=mM

Where n is the amount of the substance in moles, m is the mass of the substance, and M is the molar mass or molecular mass of the substance, which we can find by looking at the atomic mass on a periodic table so:

n(Cu)=8.882g63.546gmol1=0.139772763mol

and:

n(O)=10g8.882g15.9994gmol1=0.06987762041mol


Now we find the ratio of the copper and oxygen by dividing both values by the lowest value:

Cu:O=0.139772763mol0.06987762041mol:0.06987762041mol0.06987762041mol

=1.999535219:1

The value of 1.999535219 can be rounded to 4 significant figures to get a ratio of 2:1, as the figures in the question are given to 4 s.f.

From this ratio we can get the empirical formula of Cu2O