It’s b I just looked it up
I think the answer is a not sure tho hope u the answe
Answer:
it has made the study of chemistry systematic and easy. it acts as an aid to memory
Answer:
B) number of electrons
Explanation:
The two species:
K+ and Cl- have the same number of electrons.
A neutral atom of K has 19 electrons
A neutral atom of Cl has 17 electrons
Now,
To form K+, K will have to lose an electron and then the number of electrons becomes 18
To form Cl-, Cl will have to gain an electrons and then the number of electrons becomes 18
So, therefore, the number of electrons on both species is 18
The excited atom is positive when then neutral has no charge