Published by:
CGP EDU Academic Team
Published on: August 12, 2026
Helium has two electrons in 1s-orbital. It is converted to 
by losing one electron. Which statement is true about this ion?
A
Its spectrum resembles the hydrogen spectrum.
B
Ionisation energy of 
formed is smaller than that of He .
formed is smaller than that of He . C
The nuclear charge has decreased by one unit.
D
Ionic mass of 
is one.
is one.
Text Solution
Verified by ExpertsThe correct answer is:
A
Among the given statements, is true while other are false.
Their corrected form are
• IE of 
formed, is larger than that of He .
• From converting He to 
, the nuclear charge has increased by one unit.
• Ionic mass of 
is 4.
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