Question 1
| Element | Atomic radius (picometers) |
|---|---|
| Sodium | 186 |
| Magnesium | 160 |
| Aluminum | 143 |
| Silicon | 118 |
| Phosphorus | 110 |
| Sulfur | 103 |
| Chlorine | 99 |
The table gives the radii of atoms of Period 3 elements. Which explanation accounts for the pattern?
Regents Chemistry, January and June.
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Six topics, one three-hour test
Built on the New York State P-12 Science Learning Standards that the Regents Examination in Physical Science: Chemistry tests, with the 2025 Reference Tables. Not built for the Physical Setting/Chemistry exam.
1. Structures and Properties of Matter
2. Chemical Reactions
3. Energy
4. Waves and Electromagnetic Radiation
5. Matter and Energy in Organisms and Ecosystems
6. Engineering, Technology, and the Applications of Science
| Part | What it is | Questions and credit |
|---|---|---|
| Question clusters | 9 to 11 clusters, each built around a phenomenon with reading passages, data tables, graphs, diagrams or photos. | 45 to 55 questions |
| Multiple choice | About 60% of the questions: four answer choices. | 1 credit each |
| Constructed response | About 40% of the questions: you write your own answer. | 1 credit each |