Science Midterm Exam Review 2024

Which of the following correctly identifies a liquid based on the properties listed in the table?

• Object 1

• Object 2

• Object 3

• None of the objects have properties that represent a liquid

Answer explanation

Object 3 exhibits properties typical of a liquid, such as a definite volume but no fixed shape, allowing it to take the shape of its container. The other objects do not match these characteristics.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which of the following occurs when the temperature of a substance increases?

• The volume of the substance increases.

• The kinetic energy of its particles will increase.

• The mass of the substance will increase.

• The substance will expand.

Answer explanation

When the temperature of a substance increases, the kinetic energy of its particles will increase, causing them to move faster. This is the primary reason for changes in state and volume, but mass remains constant.

Tags

NGSS.MS-PS1-4

The following diagram represents

• a mixture of elements

• a pure substance that is a compound

• a mixture of compounds.

• a pure substance that is an element.

Answer explanation

The diagram represents a pure substance that is a compound, as it consists of two or more elements chemically combined in a fixed ratio, distinguishing it from mixtures of elements or compounds.

Tags

NGSS.MS-PS1-1

How would a mixture that is composed of mixed nuts be classified?

• Heterogeneous Mixture

• Pure Substance

• Homogeneous Mixture

• Compound

Answer explanation

A mixture of mixed nuts is classified as a heterogeneous mixture because the individual components (different types of nuts) can be seen and separated, unlike a homogeneous mixture where the composition is uniform throughout.

A laboratory investigation was conducted to learn about the physical properties of different elements. Students observed four samples and recorded their observations in the table below. Based on these properties, which element is most likely a metal?

• Element 1

• Element 2

• Element 3

• Element 4

Answer explanation

Element 4 is most likely a metal because it exhibits properties such as high conductivity, malleability, and a shiny appearance, which are characteristic of metals. The other elements do not display these metallic properties.

Students were investigating filled cans of soda to test their density in water. Which of the following is true of this investigation?

• All cans of soda are less dense than water

• Both cans of soda are more dense than water.

• Regular soda is more dense than water

• Diet soda is more dense than water

Answer explanation

Regular soda contains sugar, making it denser than water, which is why it sinks. In contrast, diet soda, which uses artificial sweeteners, is often less dense than water, allowing it to float.

Tags

NGSS.MS-PS1-2

Different cubes were tested compared to water. Based on the observations from the table above, which is a valid conclusion?

• Objects that are more dense than water will float

• Objects that are cubes will sink

• Objects that are less dense than water will sink.

• Objects that are less dense than water will float.

Answer explanation

Objects that are less dense than water will float, as they displace a volume of water equal to their weight. The other options incorrectly state the behavior of density in relation to buoyancy.

The teacher performed a demonstration for the class and mixed two liquids in a beaker. The students recorded the following observations in their journals. Based on the student observations, which evidence of a chemical change has occurred?

• Production of a precipitate

• Unexpected change in color

• Production of a gas

• Change in thermal energy

Answer explanation

The production of a precipitate indicates a chemical change, as it shows that new substances have formed from the reaction of the two liquids, which is a key sign of a chemical transformation.

Tags

NGSS.MS-PS1-2

Which of the following observations is an indication that a chemical reaction has occurred?

• Two liquids of the same color are mixed and and turn a new color.

• A pot of sugar boils and the sugar granules dissolve.

• Water boils and steam forms.

• A clear solution is frozen and a solid forms.

Answer explanation

Dissolving sugar in boiling water indicates a physical change, not a chemical reaction. The correct observation is when two liquids mix and change color, showing a chemical reaction has occurred.

Tags

NGSS.MS-PS1-2

PART A A student lightly kicks a ball across the floor. After a few seconds, the ball stops rolling. Based on the scenario, which of the following forces causes the ball to stop rolling?

• Magnetism

• Friction

• Normal Forces

• Applied Forces

Answer explanation

The ball stops rolling due to friction, which is the force that opposes the motion of the ball against the floor. Without friction, the ball would continue to roll indefinitely.

Tags

NGSS.MS-PS2-2