I think it would be 1, 4, 5! Also I love your profile picture!
The atomic mass on the periodic table represents the sum of number of protons and number of neutrons.
Atomic mass = Number of protons + number of neutrons
Hope this helps!
Answer:
D
Explanation:
According to all the principles of filling it is d
A double bond between carbon atoms is longer than a triple bond between carbon atoms.
