Calculate the mass defect for beryllium-9, the only isotope of beryllium. The mass of beryllium-9 is 9.012182 amu. The mass of a proton (p11) is 1.00728 amu; the mass of a neutron (n01) is1.00866 amu, and the mass of an electron(e10) is0.00055 amu.

Mass defect = - 0.060238 amu

Explanation:

To calculate the mass defect:

1. add up the masses of each proton and of each neutron that make up the nucleus,

Berylium 9 has;

4 protons = 4 * 1.00728 amu = 4.02912 amu

5 Neutrons = 5 * 1.00866 amu = 5.0433 amu

Sum = 9.07242 amu

2. subtract the actual mass of the nucleus from the combined mass of the components to obtain the mass defect.

Mass defect = Actual Mass - Combined mass

Mass defect = 9.012182 amu - 9.07242 amu

Mass defect = - 0.060238 amu

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer