Question

1. use a periodic table to choose the best answer.

which element pairing is most likely to react with each other?
na and k
na and br

Explanation:

Step1: Analyze the properties of elements

Metals (like Na and K) tend to lose electrons, and non - metals (like Br) tend to gain electrons.

Step2: Consider the reactivity

Na (a metal) and Br (a non - metal) are likely to react via ionic bonding (Na donates an electron to Br). Na and K (both metals) have similar electron - losing tendencies and are less likely to react with each other.

Answer:

Na and Br