Question

When moving across a period from left to right in the periodic table (excluding transition elements) which trend occurs? (1 point)
• Valence electrons increase by one.
• Valence electrons decrease by one.
• The energy levels decrease by one.
• The energy levels increase by one.

Answers

GPT-4o mini
When moving across a period from left to right in the periodic table (excluding transition elements), the trend that occurs is:

**Valence electrons increase by one.**

This is because each successive element in the same period has an additional proton and an additional electron, leading to an increase in the number of valence electrons.