Lone pairs from valence electrons
A central atom in a food packaging investigation has \(5\) valence electrons and uses \(3\) electrons in single bonds. Calculate the number of lone pairs left on the central atom. Use the diagram labels first, then answer carefully. Enter the answer and choose the interpretation that matches the chemistry.
Worked practice: chemistry evidence and answer
Use the chemical evidence first, then enter the result and interpretation that match it.
Write a full answer
Now write the response in full, in your own words — this is what the exam asks for. The AI marks it on the same moves you built above (focus, evidence, technique, judgement) and gives feedback on reasoning, evidence, and expression.