A physical change to matter can be reversed, whereas a chemical change cannot. In which of the following scenarios is a physical change taking place?

• Gas is produced when sodium mixes with water.

• A fireplace is burning wood.

• Liquid water turns to a vapor at 100°C.

• A cracker is being digested in the stomach.

Tags

NGSS.HS-PS3-4

In which of the following scenarios is a chemical change taking place?

• Gas is produced when sodium mixes with water.

• Sugar dissolves when poured into tea.

• Liquid water turns to a vapor at 100°C.

• Quartz crystal fractures when struck.

Tags

NGSS.HS-PS1-2

A state of matter that has a definite volume and shape.

• solid
• liquid
• gas
• matter

Tags

NGSS.5-PS1-3

Which of the following is an example of intensive property?

• volume

• density

• length

• mass

Which of the following is an example of an extensive property?

• weight

• density

• concentration

• temperature

What is the picture displayed?

• atom
• element
• molecule
• compound

Tags

NGSS.MS-PS1-1

Which of these is a pure substance?

• bread

• sodium chloride

• garden soil

• sea water

Which of these is a mixture?

• Salt water

• Distilled water

• A nugget of gold

• A molecule of Oxygen

Which of the following sequences corresponds to a correct trend in ionization energy?

• Cl > S > P > Al
• Sr > Ca > Mg > Be
• Rb > K > Na > Li
• Rb > Sr > I > Xe

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which of these is most electronegative?

• aluminum

• oxygen

• sulfur

• neon