Answer
63.67 g/mol
Work Step by Step
mm= molecular mass
x1 = the percent of copper in the sample by mass
x2= percent of sample of zinc by mass
percents will be used in decimal form
x1(mm1)+x2(mm2)
x1=7.36/(7.36+.51)=.935
x2=.51/(7.36+.51)=.065
Multiply the decimal by molar mass and add
.935*63.55+.065*65.38=63.67g/mol
