Question

1. what element produced the average atomic mass using the following data? mass number abundance 28 92.21% 29 4.70% 30 3.09% phosphorus aluminum germanium silicon clear all

Explanation:

Step1: Convert percentages to decimals

$92.21\% = 0.9221$, $4.70\%=0.0470$, $3.09\% = 0.0309$

Step2: Calculate average atomic mass

Average atomic mass $=28\times0.9221 + 29\times0.0470+30\times0.0309$
$=28\times0.9221+29\times0.0470 + 30\times0.0309$
$=25.8188+1.363+0.927$
$=28.1088\approx28.1$
Silicon has an average - atomic mass close to 28.1.

Answer:

D. Silicon