Grade 8 Science EOG Review Quiz

What is a physical change?

• A change in state of matter

• A change in chemical composition

• A change in color

• A change in temperature

Answer explanation

A physical change refers to a change in the state of matter, such as solid to liquid or gas. It does not involve a change in chemical composition, color, or temperature.

Tags

NGSS.MS-PS1-4

What is a chemical change?

• A change in chemical composition

• A change in state of matter

• A change in temperature

• A change in color

Answer explanation

A chemical change refers to a change in the chemical composition of a substance. It involves the rearrangement of atoms and the formation of new substances. This is the correct choice as it accurately describes a chemical change.

Tags

NGSS.MS-PS1-2

What is the most common element in the Earth’s crust?

• Oxygen

• Iron

• Silicon

• Aluminum

Answer explanation

The most common element in the Earth's crust is Silicon. It is widely abundant and forms a significant part of the Earth's composition.

Tags

NGSS.MS-PS1-1

How can a scientist, using the periodic table, find an element with properties similar to another element?

• By looking at the atomic mass

• By looking at the period number

• By looking at the atomic number

• By looking at the group number

Answer explanation

To find an element with similar properties, a scientist can look at the group number on the periodic table. The group number indicates elements with similar chemical behavior.

Chemical X has a mass of 5 grams, and chemical Y has a mass of 10 grams. If the two chemicals are mixed and a complete chemical reaction takes place, what is most likely the mass of the product?

• 20 grams

• 10 grams

• 5 grams

• 15 grams

Answer explanation

When two chemicals react, the mass of the products is equal to the sum of the masses of the reactants. Since Chemical X has a mass of 5 grams and Chemical Y has a mass of 10 grams, the total mass of the reactants is 15 grams. Therefore, the most likely mass of the product is 15 grams, which matches the correct answer choice.

Tags

NGSS.MS-PS1-5

Name two elements that belong to the same group.

• Oxygen and Nitrogen

• Carbon and Silicon

• Sodium and Potassium

• Iron and Copper

Answer explanation

Sodium and Potassium belong to the same group in the periodic table. They have similar chemical properties and react similarly with other elements.

Give an example of a synthetic material.

• Wood

• Glass

• Cotton

• Plastic

Answer explanation

Plastic is an example of a synthetic material. It is a man-made material that is created through chemical processes. Unlike natural materials like wood, glass, and cotton, plastic is not derived from plants or animals. Plastic is widely used in various industries due to its durability, versatility, and low cost.

Tags

NGSS.MS-PS1-3

Name the element that contains 6 protons, 6 neutrons, and 6 electrons.

• Carbon

• Hydrogen

• Oxygen

• Nitrogen

Answer explanation

The element that contains 6 protons, 6 neutrons, and 6 electrons is Carbon. Carbon has an atomic number of 6, which corresponds to the number of protons in its nucleus. It also has 6 electrons to balance the positive charge of the protons. The number of neutrons can vary, but in this case, it is also 6. Therefore, the correct choice is Carbon.

Tags

NGSS.MS-PS1-1

In which phase is substance easiest to compress?

• Solid

• Liquid

• Gas

• Plasma

Answer explanation

Gas is the phase in which substance is easiest to compress.

Why does ice become liquid more easily than lead?

• Ice has a higher melting point than lead

• Ice has a lower melting point than lead

• Lead is a better conductor of heat than ice

• Lead is a better insulator than ice

Answer explanation

Ice becomes liquid more easily than lead because it has a lower melting point.

Tags

NGSS.MS-PS1-4