Answer:
c. 0.30
Explanation:
One C atom has a mass of 12.0 u and one Ar atom has a mass of 40.0 u.
Let’s assume that there are n atoms of C and n atoms of Ar. Then
Mass of n C atoms = n × 12.0
Mass of n C atoms = 12.0n u
Mass of n Ar atoms = n × 40.0
Mass of n Ar atoms = 40.0n u
ratio = mass of C/mass of Ar
ratio = 12.0n/40.0n
ratio = 0.300