Question

the periodic table of the elements is shown below. cesium (cs), the circled element, is a highly reactive metal. which elements have a reactivity similar to cesium? barium (ba) and radon (rn) silver (ag) and cadmium (cd) sodium (na) and potassium (k) strontium (sr) and radium (ra)

Explanation:

Step1: Recall periodic table trends

Elements in the same group (vertical column) of the periodic table have similar chemical properties. Cesium (Cs) is in Group 1 (alkali metals).

Step2: Check each option

• Option 1: Barium (Ba) is in Group 2 (alkaline - earth metals), Radon (Rn) is in Group 18 (noble gases). Different groups, so no.
• Option 2: Silver (Ag) is in Group 11, Cadmium (Cd) is in Group 12. Different groups, so no.
• Option 3: Sodium (Na) and Potassium (K) are in Group 1 (alkali metals). Same group as Cs, so yes.
• Option 4: Strontium (Sr) and Radium (Ra) are in Group 2 (alkaline - earth metals). Different group, so no.

Answer:

Sodium (Na) and Potassium (K)