Grade 7 Science Summative Test

Why do scientists use models?

• They are exact representations of reality.

• They only exist in computer simulations.

• They are always simple and easy to understand.

• They can be used to test ideas and make predictions.

What can be a limitation of scientific model?

• They are never updated or improved.

• They are all based on real-world data.

• They are only used in physics, not other sciences.

• They cannot perfectly capture all the complexities of a system.

What resembles the Plum Pudding Model of the atom?

• A tiny, solid ball with negative charges stuck on the outside.

• A complex mathematical equation describing electron behavior.

• A miniature solar system with planets orbiting a central nucleus.

• A positively charged sphere with negatively charges scattered throughout.

Why is the Plum Pudding Model helpful for scientists?

• It shows how atoms are mostly empty space.

• It shows electrons have specific energy levels.

• It shows how atoms are indivisible particles.

• It shows the nucleus is the most massive part of the atom.

What is the characteristic of solid particles as seen in its particle model?

• Moving freely and spread far apart.

• Arranged in a specific pattern but with large gaps.

• Vibrating in place with minimal space between them.

• Flowing around each other and constantly changing positions.

What can you say about the particles of liquid in contrast with a solid?

• A predictable pattern of movement.

• Less movement and are more tightly packed.

• The same amount of movement and spacing.

• More freedom to move and more space between them.

What happens to the particles of a material being heated?

• Slightly compacted but can move

• Moves farther away from each other

• Gains more definite shape and compactness

• Nothing happens because heat is not absorbed

Which of the following shows how particles behave when heated?

• No motion

• The particles move

• The particles will become invisible

• The particles will multiply its volume

What can be seen in the physical model of the Bohr model of the atom?

• Presence of orbitals

• A cloud of electrons

• A nucleus at the center

• Nothing, just empty space

Which of the following CAN NOT be a scientific model for the atom?

• A song with lyrics full of subatomic particles and their charges.

• An image (picture, concept map, flowchart, etc.) that considers all laws of science

• A round Styrofoam colored with parts representing electrons and other subatomic particles.

• A computerized interactive game