How many valence electrons are in tc

Tc is Technetium, and it has an atomic number of 43. Its atomic configuration is [Kr] 5s(1) 4d(5) [I'm on my phone so I can't do numbers on shoulders, pretend that 1 and 5 are on the s and d's shoulder]
The outside most ring is the 4d(5), and the d orbital can hold ten electrons.
Valence electrons are electrons, in you could say the outside ring that isn't filled, the extra ones. In this case, there are 5.

Idkat all because idhducheh

Yes it would be a physical change.