The second one, vocab and definition doesn't add up
The elements in each group have the same number of electrons in the outer orbital. Or also called valence electrons. Khan academy has a great video online explaining why this happens. (It only happens for main group elements). Here is a link (sorry you can’t click it in Brainly) https://www.khanacademy.org/science/chemistry/periodic-table/copy-of-periodic-table-of-elements/v/periodic-table-valence-electrons. Feel free to message me for a better explanation, I would explain now but I’m not sure how much you know about this. If you know how to write an electron configuration you can see how all the electron configurations for the same group (not the transitional metals only the main groups) have the same number of valence electrons. I hope that helped, sorry I was vague about the explanation :)
It’s definitely B but I’m not sure
Answer:
<h2>
<em>an</em><em>swer</em><em> will</em><em> be</em><em> </em><em>D</em></h2>
<em>change</em><em> </em><em>of</em><em> </em><em>sta</em><em>te</em><em> </em><em>only</em><em> </em>
I believe the answer is: Protons and Neutrons
Protons weigh 1 amu while neutrons also weigh 1 amu. I’m not sure if they are talking about how many there is.
