A newly discovered element, Z, has two naturally occurring isotopes. 90.3 percent of the sample is an isotope with a mass of 267.8 u, and 9.7 percent of the sample is an isotope with a mass of 270.9 u. What is the weighted average atomic mass for this element?

Question

dumbcow · Answer

for weighted average, let p(x) = percent of sample and x be mass
$$w = \sum_{?}^{?} p(x)*x$$
--> (.903)(267.8) + (.097)(270.9)

anonymous · Answer

options

268.1 u 

269.0 u 
	
269.4 u 
	
270.6 u

dumbcow · Answer

do the math...i showed you the formula

anonymous · Answer

i see what you did now thanks