Question

element b has two isotopes: b - 35: atomic mass = 34.97 amu, abundance = 75.78% b - 37: atomic mass = 36.97 amu, abundance = 24.22% the average atomic mass of element b is: amu

Explanation:

Step1: Convert percentages to decimals

$75.78\%=0.7578$, $24.22\% = 0.2422$

Step2: Calculate contribution of B - 35

$34.97\times0.7578=26.499266$

Step3: Calculate contribution of B - 37

$36.97\times0.2422 = 8.954134$

Step4: Find average atomic mass

$26.499266+8.954134 = 35.4534\approx35.45$

Answer:

$35.45$