8th Grade Science Concepts Review

The video tutorial covers various science topics for 8th graders, including calculating the density of an iron cube, identifying cork by its density, understanding atomic structure, and discussing the properties of magnesium oxide. It also explains how to identify carbon in acetic acid, locate nonmetals on the periodic table, and compare the conductivity and properties of metals and nonmetals.

What is the density of an object that has a mass of 64 grams and displaces 8 milliliters of water?

• 1 gram per milliliter

• 8 grams per milliliter

• 8 milliliters per gram

• 64 grams per milliliter

Which material is likely to be cork based on its density?

• Density of 26 grams per milliliter

• Density of 2.6 grams per milliliter

• Density of 0.24 grams per milliliter

• Density of 89 grams per milliliter

Tags

NGSS.MS-PS1-2

What property allows cork to float in water?

• Its density is less than 1 gram per milliliter

• Its weight is lighter than water

• Its mass is less than water

• Its volume is greater than water

What best describes the structure of an atom?

• A core of electrons and neutrons surrounded by protons

• Protons and electrons grouped in an alternating pattern

• A core of protons and neutrons surrounded by electrons

• Protons and electrons grouped together in a random pattern

Tags

NGSS.MS-PS1-1

Why do magnesium and oxygen have different properties from magnesium oxide?

• Because magnesium oxide is a metal

• Because they are in different states of matter

• Because magnesium oxide is a compound with different properties

• Because oxygen is a gas

Tags

NGSS.MS-PS1-5

What is the result of combining two or more elements?

• An alloy

• A compound with different properties

• A solution

• A mixture

Tags

NGSS.MS-PS1-5

What element is indicated by the capital 'C' in the acetic acid molecule?

• Calcium

• Cobalt

• Copper

• Carbon

Tags

NGSS.MS-PS1-1

Where are non-metals located on the periodic table?

• In the center of the table

• To the left of the staircase line

• Directly below the staircase line

• To the right of the staircase line

Which class of elements is best at conducting electricity?

• Metals

• Metalloids

• Noble gases

• Non-metals

Compared to non-metals, metals tend to have:

• Lower conductivity and higher melting points

• Greater conductivity and higher melting points

• Higher density and lower melting points

• Lower melting points and greater conductivity