Periodic table groups

Question

A student wants to predict which unfamiliar element may share chemical properties with a known element. Where on the periodic table should the student look first?

1. AIn the same vertical group✓ Correct

   Elements in a group generally show similar chemical behavior.

2. BAnywhere in the same horizontal period✗ Incorrect

   A horizontal period contains elements across a range of chemical properties.

3. COnly in the bottom detached rows✗ Incorrect

   Those rows are specific series, not a universal match for every element.

4. DOnly among elements with the same atomic number✗ Incorrect

   Atomic number identifies an element; a different element has a different atomic number.

Answer

A. In the same vertical group

Rationale

A vertical group is a useful starting point for comparing chemical behavior. Similarity is a general pattern, so an actual prediction still needs checking.