Quick question here:

Which has the higher reactivity, Calcium or Potassium? Is it calcium?

No it is in fact Potassium

Oh! OK, thanks.

No problem :)

To determine which element has higher reactivity, we need to compare their positions in the periodic table. Reactivity generally increases as you move down a group and decreases as you move across a period.

Calcium (Ca) is located in Group 2, also known as the alkaline earth metals, while Potassium (K) is located in Group 1, known as the alkali metals. Alkali metals are generally more reactive compared to alkaline earth metals.

Therefore, Potassium (K) has higher reactivity than Calcium (Ca).