Question detail
Explain how the first ionisation energy changes across Period 3 and provide a reason for this trend.
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
Question
Type
exam_style
Style
Topic
Periodicity
Question
Explain how the first ionisation energy changes across Period 3 and provide a reason for this trend.
Answer
The first ionisation energy increases across Period 3 from sodium to argon. This is due to the increasing nuclear charge, which results in a stronger attraction between the nucleus and the outer electrons, making them harder to remove.
Explanation
This answer is strong because it accurately describes the trend in first ionisation energy and provides a clear reason related to nuclear charge. The question tests the understanding of periodic trends and the underlying atomic structure.
Common mistake
Misunderstanding Ionisation Energy Trends
Students often confuse the trend in first ionisation energy across Period 3 with atomic radius, thinking that ionisation energy decreases as atomic radius increases.
To clarify, remember that first ionisation energy increases across Period 3 due to increased nuclear charge attracting electrons more strongly. Use the formula for ionisation energy trends: as atomic number increases, ionisation energy increases because of greater effective nuclear charge. Therefore, the correct trend is that first ionisation energy increases across Period 3.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.