MCQ
In the nucleus of $_{20}C{a^{40}}$ there are
- A$40$ protons and $20$ electrons
- B$20$ protons and $40 $ electrons
- ✓$20 $ protons and $20 $ neutrons
- D$20 $ protons and $40 $ neutrons
✓
Answer
Correct option: C.
$20 $ protons and $20 $ neutrons
c
(c) $P = \,$ $20$, mass no $(a) = 40$
(c) $P = \,$ $20$, mass no $(a) = 40$
$N = \,$ $A-P = $ $40 - 20 = 20$
$P = N = 20.$
.
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