Question 257: Atoms & Nuclei

Question

Given the masses of various atomic particles
mp = 1.0072 u, mn = 1.0087 u, me = 0.000548 u,
$${m_{\overline v }}$$ = 0, md = 2.0141 u, where p $$ \equiv $$ proton,
n $$ \equiv $$ neutron, e $$ \equiv $$ electron, $$\overline v $$ $$ \equiv $$ antineutrino and
d $$ \equiv $$ deuteron. Which of the following process is
allowed by momentum and energy
conservation?

Accepted Answer

n + n $$ 	o $$ deuterium atom (This is incorrect)
Correct is n + p $$ 	o $$ d + $$\gamma $$
p $$ 	o $$ n + e
+
+ $$\overline v $$
(This is incorrect as mass is increasing)
e
+
+ e
-
$$ 	o $$ $$\gamma $$ (This is incorrect)
Correct is e
+
+ e
-
$$ 	o $$ 2$$\gamma $$

Answer

n + n $$ 	o $$ deuterium atom
(electron bound to the nucleus)

Answer

n + p $$ 	o $$ d + $$\gamma $$

Answer

p $$ 	o $$ n + e+ + $$\overline v $$

Answer

e+ + e- $$ 	o $$ $$\gamma $$

Atoms & Nuclei

Choose the correct answer: