Each column is called a group<span>. The elements in each </span>group have<span> the same number of electrons in the outer orbital. Those outer electrons are also called valence electrons.</span>
The potential energy of the products is higher than the potential energy of the reactants.
Potassium is placed where it is based on its properties and it's reactivity. It's also placed there based on it's atomic number.
CaBr2(s) Ca+2(aq)+2Br-(aq) which means, <span>Solid is turning into free ions so entropy is increasing .</span>
Here is the answer for the three of them
<span>N20 = 16 e-
</span><span>SeCl2 =20
</span><span>PBr3 = 26
Remember that t</span><span>o find the valence electrons in an atom you need to identify what group the element is in. An element in group 1A has 1 valence electron. If the element is in group 2A, then it has two valence electrons.</span>
