Atomic Theory — Unit test Answers

If two items are equal in size, the denser one will

Four students made statements about a tennis ball they were using in a lab.Which student made a mistake in her statement?

Which is the process by which a gas changes to a solid?

Which would show an example of how physical changes are reversible?

The density of an object is .835 g/cm3. If its volume is 34 cm3, what is the mass of the object? (Density: D = )

Which describes a feature of the physical changes of all substances?

During which change of state do atoms lose energy?

A substance occupies one half of an open container. The atoms of the substance are closely packed but are still able to slide past each other.What is most likely the phase of the substance?

Sari is studying four different samples of materials. This table shows the mass and volume of the samples.

The descriptions below explain two ways that water is used by plants on a sunny day.I. In a process called transpiration, some liquid water in leaves changes to water vapor. The water vapor is released into the air through tiny pores in the leaves. This allows more liquid water from the soil to be pulled up the roots and stem to replace water lost from the leaves.II. Plants use some of this water in leaves in a process called photosynthesis. During photosynthesis, water and carbon dioxide break apart and recombine to form two new substances, oxygen and glucose.

Abi measures the volume and weight of four objects and records his data in this table.Which object has the most mass?

Which procedure would best allow a scientist to observe a chemical property of hydrochloric acid (HCl) solution?

Which is a characteristic of atoms?

Tijuan mixed a solid and a liquid together in a beaker. He determined that a chemical change occurred.

Suppose that a substance in a beaker is heated over a burner in a science lab. Which observation would most likely indicate that a chemical change has occurred in the substance?

Which is the amount of matter in an object?

Venn diagrams are used for comparing and contrasting different topics. The overlapping sections show characteristics that the topics have in common, and the sections that are unique to each topic show the characteristics apply to only that topic.

Which is most likely a physical change?

The diagram shows changes of state between solid, liquid, and gas. The atoms of a substance gain energy during a change of state. Before the change, the atoms are close together and cannot slide past one another. After the change, the substance can fill its container.

Rahul sees a flock of birds. He watches as the flying birds land in neat little rows on several power lines. Which change of state does the motion of the birds most closely model?