An example of the neutron absorption reaction is .
1 0 n+10 5 B-->7 3 Li+ 4 2 He
The rest masses of each particle in atomic mass units (u) are
1 0 n= 1 u
10 5 B=10 u
7 3 Li =7 u
4 2 He= 4 u
where 1u=1.66x10^-27 kg.
calculate Q
Q= in MeV
I have the same question please someone help me solve this. Thank you
To calculate the Q value for the given neutron absorption reaction, we need to use the equation:
Q = (m_initial - m_final) * c^2
where:
- Q is the Q value
- m_initial is the initial mass of the reactants
- m_final is the final mass of the products
- c is the speed of light in vacuum (approximately 3x10^8 m/s)
Let's calculate the Q value step by step:
Step 1: Determine the initial mass (m_initial):
The initial mass (m_initial) is the sum of the masses of the reactants:
m_initial = mass of neutron (1 u) + mass of boron-10 (10 u)
m_initial = 1 u + 10 u = 11 u
Step 2: Determine the final mass (m_final):
The final mass (m_final) is the sum of the masses of the products:
m_final = mass of lithium-7 (7 u) + mass of helium-4 (4 u)
m_final = 7 u + 4 u = 11 u
Step 3: Calculate the Q value using the equation:
We have the values for m_initial and m_final. Additionally, we need the value of the speed of light (c) in meters per second.
c = 3 x 10^8 m/s
Now we can plug in the values and calculate Q:
Q = (m_initial - m_final) * c^2
= (11 u - 11 u) * (3 x 10^8 m/s)^2
= 0 * (9 x 10^16 m^2/s^2)
= 0 J
Since the Q value is zero, there is no excess energy released or absorbed during this neutron absorption reaction.
To convert the Q value from joules (J) to megaelectron volts (MeV), we can use the conversion factor 1 MeV = 1.6 x 10^-13 J:
Q_in_MeV = Q / (1.6 x 10^-13 J/MeV)
= 0 J / (1.6 x 10^-13 J/MeV)
= 0 MeV
Therefore, the Q value for this neutron absorption reaction is 0 MeV.