Question

1. a new element x is discovered with two common isotopes. you find that 40% of element x exists as x-150 (atomic mass) and 60% exists as x-156. what is the average atomic mass of x? show all your work on your paper. *hint: dont round until the final answer. round to the nearest tenth. amu

Explanation:

Step1: Calculate contribution of X-150

The abundance of X-150 is 40% (or 0.4) and its atomic mass is 150 amu. So the contribution is \( 0.4 \times 150 \).
\( 0.4 \times 150 = 60 \)

Step2: Calculate contribution of X-156

The abundance of X-156 is 60% (or 0.6) and its atomic mass is 156 amu. So the contribution is \( 0.6 \times 156 \).
\( 0.6 \times 156 = 93.6 \)

Step3: Sum the contributions

Add the two contributions together to get the average atomic mass: \( 60 + 93.6 \).
\( 60 + 93.6 = 153.6 \)

Answer:

153.6