The actual mass of a Cl-37 atom is 36.966 amu. Calculate the mass defect in amu per atom for Cl-37.

To calculate the mass defect for an atom of Cl-37, we first need to understand what mass defect means. Mass defect is the difference between the actual mass of an atom and the sum of the masses of its protons, neutrons, and electrons if they were counted separately. This difference comes about due to the binding energy that holds the nucleus together, which corresponds to a mass according to Einstein's equation E=mc^2.

For Cl-37, the atom consists of 17 protons, 20 neutrons, and 17 electrons (since it's a neutral atom). The approximate masses of these particles are as follows:

- Mass of 1 proton ≈ 1.007825 amu - Mass of 1 neutron ≈ 1.008665 amu - Mass of 1 electron ≈ 0.000548 amu

First, let's calculate the combined mass of the protons, neutrons, and electrons.

Protons (17 protons x 1.007825 amu/proton) = 17.132925 amu Neutrons (20 neutrons x 1.008665 amu/neutron) = 20.1733 amu Electrons (17 electrons x 0.000548 amu/electron) ≈ 0.009316 amu

Now, add these values to get the total mass if the components were separate:

Total mass = 17.132925 amu + 20.1733 amu + 0.009316 amu Total mass ≈ 37.315541 amu

Now, we have the actual mass of Cl-37 which is 36.966 amu, and we've calculated the sum of the masses of its individual components to be approximately 37.315541 amu. The mass defect can be found by subtracting the actual mass from the total mass calculated above:

Mass defect = Total mass - Actual mass Mass defect ≈ 37.315541 amu - 36.966 amu Mass defect ≈ 0.349541 amu

Therefore, the mass defect of a Cl-37 atom is approximately 0.349541 amu.