What is the $Q$-value of the reaction $P + \ ^{7}Li\ \rightarrow \ ^{4}He\ + \ \ ^{4}He$ The atomic masses of $\ ^{1}H,\ \ ^{4}He\ and\ \ ^{7}Li$ are 1.007825 u, 4.002603 u and 7.016004 u respectively

Question

Dr. Abubacker · Accepted Answer

(a) The total mass of the initial particles
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ m$$_{i}$$=$1.007825 +7.016004
= 8.023829 u
and the total mass of final particles
$\ \ \ \ \ \ \ \ \ \ \ \ m_{f}$ = 2 $	imes$ 4.002603 =8.005206 u
Difference between initial and final mass of particles
$\ \ \ \ \ \ \ \ \ \mathrm{\Delta}m\  = \ m_{i}\  - \ m_{f}$ = 8.023829 - 8.005206
= 0.018623 u
The $Q$-value is given by
$\ \ \ \ \ \ Q\  = \ (\mathrm{\Delta}m)c^{2}$
= 0.018623 $	imes$ 931.5 =17.35 MeV

Q. What is the $Q$-value of the reaction $P + \ ^{7}Li\ \rightarrow \ ^{4}He\ + \ \ ^{4}He$ The atomic masses of $\ ^{1}H,\ \ ^{4}He\ and\ \ ^{7}Li$ are 1.007825 u, 4.002603 u and 7.016004 u respectively

Explanation

Reviewed by Dr. Abubacker

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