Answer:
If an atom has the same number of electrons as protons, it is a neutral atom.
Explanation:
The reactivity of metals increases as you move left in a period and as you move down in a group, so Marie needs to know the period and group of the element inside each box. Boxes that show locations in groups 1 or 2 or in period 8 contain the most reactive elements.
<span>when the temperature is warm, the particles move faster and the gas is expanding and pushing on the walls of the item, like for example, a NYPD float balloon. If the gas expands too much, the balloon will explode</span>
The Lewis bases are those which can donate electron pair to an acceptor. These electrons can be a pair of electron that is a lone pair, a negative charge or electrons in a 
-bond.
- In
, the presence of -bond make it a Lewis base. - In
, the presence of negative charge makes it a Lewis base. - In
, the presence of lone pair on nitrogen makes it a Lewis base. - In
, there is no lone pair, no -bond, no negative charge so it is not a Lewis base.
Hence, , , and are Lewis bases.
