Question

Complete the following reactions. Determine their Q-values in MeV. State whether they are endothermic or exothermic. If endothermic, determine their threshold energies in MeV.

a. 2 H(n,γ)

b. 9 Be(n,α)

c. 108Ag(n,γ)

d. 14N(α,p)

e. 238U(γ,n)

Answer 1

(a) This reaction can be represented as

Q-Value for a reaction can be written as

for the above reaction, the Q-value is

If the Q-value is positive the reaction is said to be exothermic and if the Q-value is negative then the reaction is said to be endothermic.

the reaction is exothermic as Q>0.

(b) As I know, that equation should be 9Be(a,n) instead of 9Be(n, a)

The complete equation is

Q-value

This reaction is also exothermic as Q>0.

(d)

This reaction is endothermic as Q<0.