Virginia SOL PS.2

PS.2 is a Standards of Learning science standard. These are the key ideas and practices under it.

• PS.2.a

  our understanding of atoms has developed over time

• PS.2.b

  the periodic table can be used to predict the chemical and physical properties of matter

• PS.2.c

  the kinetic molecular theory is used to predict and explain matter interactions.

01

What Students Need to Do

Students explain how evidence changed atomic models over time. They use periodic table patterns to predict properties of elements. They use particle motion, spacing, and collisions to explain states of matter, diffusion, temperature, and pressure.

02

What Mastery Looks Like

Students connect major atomic models to the evidence that replaced earlier ideas. They use an element’s location to predict properties such as metallic behavior and reactivity. Their particle diagrams accurately show motion and spacing in solids, liquids, and gases.

03

Common Misconceptions

Students may confuse atomic number with atomic mass or read groups and periods backward. They may think atoms have the same properties as a visible sample of an element. They often think particles expand when heated or stop moving in a solid.

04

How to Assess It

Give an exit ticket with three tasks: identify an element from periodic table clues, revise an outdated atomic model, and draw gas particles before and after heating.

1. 01

   Build models of carbon, sodium, and chlorine with beads, then compare their proton, neutron, and electron counts.

2. 02

   Write a short claim explaining how new evidence changed atomic models from Dalton’s model to the electron cloud model.

3. 03

   Play periodic table bingo using clues about groups, periods, valence electrons, metals, and likely properties.

4. 04

   Use particle motion to explain why perfume spreads across a room and tire pressure increases on a hot day.

• 5.7.a

  matter is composed of atoms;

• 5.7

  The student will investigate and understand that matter has properties and interactions. Key ideas include

• PS.3

  The student will investigate and understand that matter has properties and is conserved in chemical and physical processes. Key ideas include

• 6.5

  The student will investigate and understand that all matter is composed of atoms. Key ideas include