2024 Science 8th STAAR Released Questions

An equation for a chemical reaction is shown. NaOH + HCl → NaCl + H₂O Which statement provides evidence that mass is conserved in the reaction?

• Two new substances are formed in the products.

• Water is one of the products, but not one of the reactants.

• Two hydrogen atoms are in the reactants, and two hydrogen atoms are in the products.

• One chlorine atom pairs with one sodium atom in the products, and one chlorine atom pairs with one hydrogen atom in the reactants.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The chemical formula for methane is CH₄. Which statement describes the atoms present in FOUR molecules of methane?

• Four molecules of methane would contain 1 atom of carbon and 4 atoms of hydrogen.

• Four molecules of methane would contain 4 atoms of carbon and 1 atom of hydrogen.

• Four molecules of methane would contain 4 atoms of carbon and 16 atoms of hydrogen.

• Four molecules of methane would contain 16 atoms of carbon and 16 atoms of hydrogen.

Tags

NGSS.MS-PS1-1

Matter can undergo physical or chemical changes. Which of these are examples of physical changes? Select TWO correct answers.

• Burning wood

• Breaking an egg

• Cooking an egg

• Freezing a popsicle

• Rusting iron

Tags

NGSS.MS-PS1-4

A student bounces a basketball off the gym floor. Which statement correctly describes the action-reaction force pair that causes the ball to bounce?

• The gym floor pushes up on the ball as the ball pushes down on the floor with an equal amount of force.

• The gym floor pushes up on the ball with a greater amount of force than the ball pushes down on the floor.

• The gym floor pushes up on the ball as gravity pulls down on the ball with an equal amount of force.

• The gym floor pushes up on the ball with a greater amount of force than gravity pulls down on the ball.

Tags

NGSS.MS-PS2-1

This question has two parts. The mass, applied force, and frictional force for four carts are shown in the table. Cart | Mass (kg) | Applied Force (N) | Frictional Force (N) W | 5 | 15 | 10 X | 10 | 15 | 10 Y | 5 | 30 | 15 Z | 10 | 30 | 15 Part A Based on the data table, which cart has the lowest acceleration?

• W

• X

• Y

• Z

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

This question has two parts. The mass, applied force, and frictional force for four carts are shown in the table. Cart | Mass (kg) | Applied Force (N) | Frictional Force (N) W | 5 | 15 | 10 X | 10 | 15 | 10 Y | 5 | 30 | 15 Z | 10 | 30 | 15 Part B Which statement BEST explains the correct answer to Part A?

• The cart will have the lowest acceleration if it has a larger mass and its applied force and friction have the greatest sum.

• The cart will have the lowest acceleration if it has a smaller mass and its applied force and friction have the greatest sum.

• The cart will have the lowest acceleration if it has a larger mass and has the least difference between its applied force and friction.

• The cart will have the lowest acceleration if it has a smaller mass and has the least difference between the applied force and friction

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Which graph represents a baseball player accelerating away from a base located at the origin?

• A

• B

• C

• D

Tags

NGSS.MS-PS3-1

Which statement BEST describes the kinetic and potential energies of the cart at Location X compared with the kinetic and potential energies of the cart at Location Y?

• The cart has more potential energy and less kinetic energy at Location X than it has at Location Y.

• The cart has less potential energy and more kinetic energy at Location X than it has at Location Y.

• The cart has the same amounts of potential energy and kinetic energy at Location X as it has at Location Y.

• The cart has more potential energy and kinetic energy at Location X than it has at Location Y.

Tags

NGSS.MS-PS3-2

NGSS.MS-PS3-5

A group of students was conducting an investigation with plants. One group of plants was placed inside a closet. The other group of plants was placed next to a window. After two weeks, the plants next to the window were taller and healthier than the plants in the closet. Which statement BEST explains the difference in plant growth?

• The plants next to the window were able to convert more light energy into chemical energy.

• The plants next to the window were able to convert more thermal energy into light energy.

• The plants next to the window were able to convert more thermal energy into mechanical energy.

• The plants next to the window were able to convert more light energy into electrical energy.

Tags

NGSS.MS-LS1-5

NGSS.MS-LS1-6

How do fossil records support the theory of plate tectonics?

• Similar fossils are found on the same continent at different time periods.

• Similar fossils are found on various modern continents.

• Different fossils are found on the same continent during the same time period.

• Fossils found along coastal regions of modern continents are unique

Tags

NGSS.MS-ESS2-3