Energy and Mass defect

Question 1

What is Einstein’s mass-energy equivalence principle?

Answer 1

E=mc 2
states that mass can be converted into energy. A small amount of mass releases a huge amount of energy because c (speed of light) is very large. 1 kg of mass = 9×10169×10 16J of energy.

Question 2

What is binding energy?

Answer 2

The binding energy of a nucleus is the amount of energy required to completely separate all the nucleons (protons and neutrons) from the nucleus.
It represents the strength of the strong nuclear force holding the nucleus together.
When a nucleus is formed, some mass is converted into energy (via e=mc2), which is released as binding energy.

Question 3

What is the concept: binding energy per nucleon?

Answer 3

Binding energy per nucleon is the total binding energy of a nucleus divided by the number of nucleons (protons + neutrons).
It shows the average energy needed to remove one nucleon from the nucleus, or how tightly each nucleon is bound.

A higher binding energy per nucleon means a more stable nucleus (e.g., Iron-56 has one of the highest binding energies per nucleon, making it very stable).

Question 4

What is a nucleon?

Answer 4

A nucleon is any particle inside the nucleus, meaning it can be either a proton or a neutron.

Question 5

What is the concept of mass defect?

Answer 5

The total mass of individual nucleons is greater than the actual mass of the nucleus. (it doesnt add up so we call the missing a mass defect).

This “missing” mass is called the mass defect, which is converted into binding energy.

Question 6

whats the formula for calculating a neuclons binding energy?

Answer 6

find actual mass - amu to kj - electron. proton + neutron - actual mass. sub into e=mc2 then reverse convert J to MEV - Note 1 mev = 10^6 of 1ev, therefore take it to the power of -13 not -19

Question 7

what’s nucleur fission?

Answer 7

In nuclear fission, heavy atoms absorb a neutron and split their nuclei into two smaller parts to reach greater stability.
This process releases excess energy, radiation, and free neutrons.

Looking at the binding energy per nucleon graph, heavy elements are less stable. Splitting them makes the new nuclei more stable and releases energy in the process.

Question 8

What’s nucleur fusion?

Answer 8

Nuclear fusion is when two light nuclei combine to form a heavier and more stable nucleus.
The new nucleus has slightly less mass than the original two, and the missing mass is converted into energy using
𝐸
=
𝑚
𝑐
2
E=mc
2
.

Question 9

How do elements try to move toward Iron-56, the most stable nucleus?

Answer 9

Light Elements (Low Mass Number) → Use Fusion

If a nucleus is small (like Hydrogen or Helium), it undergoes fusion to combine into a larger nucleus.
This increases the binding energy per nucleon, making it more stable.
Example: Hydrogen fuses into Helium in the Sun.
2️⃣ Heavy Elements (High Mass Number) → Use Fission

If a nucleus is too heavy (like Uranium-235), it undergoes fission to split into smaller, more stable nuclei.
This moves it closer to Iron-56, releasing energy.
Example: Uranium-235 undergoes fission in nuclear reactors.
3️⃣ Unstable Nuclei (Anywhere on the Graph) → Use Radioactive Decay

If a nucleus is not stable, it emits alpha, beta, or gamma radiation until it reaches a stable state.
Example: Carbon-14 decays via beta decay to become Nitrogen-14.