How many molecules of aspirin (formula mass aspirin = 180 amu) are in a 0.250-gram sample?

1 Answer
May 15, 2018

Answer:

Take the quotient...#"mass"/"molar mass"#...and,,,,

Explanation:

And so, for #C_9H_8O_4# we gots a molecular mass of #180.16*g*mol^-1#...

And so #"moles of aspirin"=(0.250*g)/(180.16*g*mol^-1)=0.001388*mol#

And to get the number of molecules we simply multiply this molar quantity by the #"Avocado number"#....

#0.001388*molxx6.02214xx10^23*mol^-1=8.36xx10^20# individual aspirin molecules....