8th Grade Science Final

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.

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

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

Tags

NGSS.MS-PS1-5

Which statement describes an action that most likely resulted in a chemical reaction?

• A pan of water was heated on a stove, and steam formed.

• A liquid was mixed with another liquid, and a precipitate formed.

• A liquid was sprayed into the air, and a sweet odor was smelled.

• A child blew through a wand filled with soap, and bubbles were produced

Tags

NGSS.MS-PS1-2

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

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

• 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 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

Which action represents a conversion of chemical energy into mechanical energy?

• Pancakes reheated in a microwave oven

• Soup beginning to boil on a stove

• A grasshopper jumping from a predator

• Sunlight melting an icicle

Which of the following forces directly affect the block’s motion both before and after the block has been released?

• Gravity and normal force

• Gravity and friction

• Normal force and tension

• Gravity, normal force, and friction

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

NGSS.MS-PS2-4

Carts of different masses are pulled along a flat surface. The table shows some variables for each cart. Which two carts experience the same net force?

• Carts 1 and 2

• Carts 1 and 3

• Carts 2 and 3

• Carts 2 and 4

Tags

NGSS.MS-PS2-2

The image shows a roller coaster cart moving along a track. 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

NGSS.MS-LS2-1

Which statement best describes the location of the sun in the Milky Way galaxy?

• The sun is located in the center of a spiral-shaped galaxy.

• The sun is located off the center of an elliptical-shaped galaxy.

• The sun is located on an arm of a spiral-shaped galaxy.

• The sun is located on an arm of an elliptical-shaped galaxy.