Generally, anions have greater electron affinity than cations. Hence, they have more positive values for this electron affinity. This means that the higher the electron affinity, the greater its positive value
Electron affinity increases across a period. Thus, it is expected that chlorine has the highest value
When your cooking, or baking a cake. For example, If you bake a cake you are adding ingredients to the cake. When you still the cake into the oven all the ingredients are reacting to each other, causing a chemical reaction.