What Causes the Mass Defect in a 15N Nucleus?

[pveclipse96]

What is the mass defect of the 15N nucleus?

My attempt:

15-7=8
7(1.008665)+8(1.0078225)-14.003074
=1.120161

the answer needs to be in u so i don't know if this makes a difference or not but for some reason it is not working

 

[alxm]

Why are you using the number 14.003074? That's the mass of 14N. The mass defect is the real mass (of 15N) minus the mass of the constituent neutrons and protons.

 

[charng]

The mass defect of a nucleus is a measure of the difference between the mass of an individual nucleus and the sum of the masses of its constituent particles (protons and neutrons). This difference arises due to the binding energy that holds the nucleus together. The higher the binding energy, the lower the mass defect of the nucleus.

To calculate the mass defect of a specific nucleus, we need to know the mass numbers of its constituent particles and the mass of the nucleus itself. In this case, we are looking at the 15N nucleus, which has a mass number of 15. The mass of a proton is 1.007276 u and the mass of a neutron is 1.008665 u. Therefore, the mass of the 15N nucleus can be calculated as follows:

15(1.008665) + (15-7)(1.007276) = 14.007074 u

Since the actual measured mass of the 15N nucleus is 14.003074 u, the mass defect can be calculated as follows:

Mass defect = 14.007074 u - 14.003074 u = 0.004 u

This means that the mass of the 15N nucleus is 0.004 u less than the sum of the masses of its constituent particles. This difference is due to the binding energy of the nucleus, which is responsible for holding its particles together. The higher the binding energy, the lower the mass defect and the more stable the nucleus is.

 

[charng]

on my computer

I can explain the concept of mass defect and calculate the mass defect of a specific nucleus. The mass defect of a nucleus refers to the difference between the actual mass of the nucleus and the sum of the masses of its individual protons and neutrons. This difference is due to the binding energy that holds the nucleus together.

In the case of the 15N nucleus, it has a total of 15 nucleons (7 protons and 8 neutrons). The mass of each proton is approximately 1.008665 u and the mass of each neutron is approximately 1.0078225 u. Therefore, the sum of the masses of the nucleons in the 15N nucleus would be (7 x 1.008665) + (8 x 1.0078225) = 14.003074 u.

However, the actual mass of the 15N nucleus is measured to be 15.00010897 u. This means that the mass defect of the 15N nucleus is the difference between these two values, which is approximately 1.120161 u.

The mass defect is an important concept in nuclear physics as it is directly related to the binding energy of the nucleus. A higher mass defect indicates a stronger binding energy, which means that the nucleus is more stable. In the case of the 15N nucleus, its relatively small mass defect suggests that it is a relatively stable nucleus. This information can be useful in understanding the properties and behavior of different nuclei.