Question

1. calculate the mass of element x. then use the periodic table to identify the element.

isotope\tpercent abundance\tmass (amu)
27x\t92.23\t27.977
28x\t4.67\t28.976
29x\t3.10\t29.974

Explanation:

Step1: Multiply mass by percent

$27.977\times0.9223$ = 25.8041871

Step2: Multiply second - mass by percent

$28.976\times0.0467$ = 1.3531792

Step3: Multiply third - mass by percent

$29.974\times0.0310$ = 0.929194

Step4: Sum results

25.8041871 + 1.3531792+ 0.929194 = 28.0865603

Answer:

28.09 amu (rounded to two decimal places)