Answer: Nuclear charge increases while electrons are added to the same shell.
- A Nuclear charge increases while electrons are added to the same shell
- B The number of occupied electron shells increases steadily in typical laboratory settings
- C Electron shielding from inner shells increases sharply under usual circumstances
- D Atomic mass decreases steadily across the period according to most researchers
Correct answer: A. Nuclear charge increases while electrons are added to the same shell
Explanation: Increasing nuclear charge across a period pulls electrons closer without adding a new shell.
The complete modern periodic table (118 elements). Image: Cepheus et al., Public Domain, via Wikimedia Commons.
Concept context
The periodic table organises all 118 elements by atomic number and similar properties. Study periodic trends like atomic radius, ionization energy, and electronegativity, and learn how an element's position predicts its behaviour.
Read the full Classification of Elements and Periodicity in Properties notes →