Question detail
What is the trend in first ionisation energy across Period 3?
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
MCQ
Type
practice
Style
Topic
Periodicity
Question
- A. It decreases
- B. It increases
- C. It remains constant
- D. It fluctuates
Answer
It increases
Explanation
The first ionisation energy increases across Period 3 due to the increasing proton number, which results in a stronger attraction between the nucleus and the outer electrons, making them harder to remove.
Common mistake
Misunderstanding Proton Number
Students often confuse atomic number with mass number when explaining how proton number determines periodic table position.
Remember that the proton number (atomic number) is the number of protons in the nucleus of an atom and directly determines the element's position in the periodic table. For example, for carbon (C), the atomic number is 6, meaning it has 6 protons, placing it in group 14 and period 2.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.