Answer: They have different properties that repeat across the next period
Step-by-step explanation:
Elements are distributed in groups and periods in a periodic table.
Elements in period are arranged in order of increasing atomic numbers, thus have different valence electrons and thus have different properties.
Elements that belong to same groups will show similar chemical properties because they have same number of valence electrons.
Thus as the elements are arranged such that the elements with similar chemical properties occur after a regular interval, it is true that the elements in the period have different properties that repeat across the next period.