Answer:
Δm = 3.0684
Explanation:
Data Given:
Atomic number of lithium = 3
Atomic mass of lithium = 7.0144 amu
Mass of 1 proton = 1.0073 amu
Mass of 1 neutron = 1.0087 amu
Solution:
Mass Defect:
Mass defect is the difference of mass number of an atom and its atomic number.
Formula used
Δm = [Z (mass of proton + mass of nutron) + ( A − Z ) mass of nutron] − m of atom
where:
Δm = mass defect (amu)
Z = atomic number
A = mass number
Put values in formula
Δm = [3 ( 1.0073 amu + 1.0087 amu) + ( 7 − 3 ) 1.0087 ] − 7.0144
Δm = [3 (2.016) + (4) 1.0087 ] − 7.0144
Δm = [(6.048) + (4.0348) ] − 7.0144
Δm = 10.0828 − 7.0144
Δm = 3.0684
