S8P1A

Ammonia can be represented by the chemical formula NH₃. Which of the following best describes ammonia?

• an atom

• a compound

• an element

• a mixture

Tags

NGSS.MS-PS1-1

An unknown substance is provided in a science class. It consists of particles that are different colors and different sizes. The particles are unevenly distributed throughout the substance. The substance is ___________.

• an element

• a compound

• a homogeneous mixture

• a heterogeneous mixture

S8P1a A diagram of a particle is shown above. The particle is most likely _________.

• an atom

• a molecule

• a homogeneous mixture

• a heterogeneous mixture

Tags

NGSS.MS-PS1-1

Which is an example of a mixture?

• water

• hydrogen gas

• a blueberry muffin

• a spoon made of the element silver

S8P1e The model shows a neutral atom. How many protons are in this atom?

• 2

• 4

• 5

• 9

Tags

NGSS.MS-PS1-1

S8P1e In which period, or row, of the periodic table would you find this element?

• Period 2

• Period 4

• Period 6

• Period 7

Tags

NGSS.MS-PS1-1

When enough heat is added to liquid water, it boils, and bubbles of water vapor rise to the surface and into the air. Which type of change is this and why?

• a chemical change because gas is produced

• a chemical change because heat is produced

• a physical change because the identity fo the substance changes

• a physical change, because the substance changes state

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

During a chemical reaction, methane (CH₄) and oxygen (O₂) combine to produce carbon dioxide (CO₂) and water (H₂O). The balanced chemical equation identifies the reactants and products for this reaction, along with some of their masses.

CH₄ + 2O₂ --> CO₂ + 2H₂0

16g + ? --> 44g + 36 g

Which mass of oxygen (O₂) is required for this reaction to occur?

• 16 g

• 36 g

• 44 g

• 64 g

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

• A) an atom

• B) a compound

• C) an element

• D) a mixture

Tags

NGSS.MS-PS1-1

A student mixes sand and salt in a beaker. Which of the following best describes the mixture?

• A) an element

• B) a compound

• C) a homogeneous mixture

• D) a heterogeneous mixture