Chemical Changes in the Lab

Which lab experiments below describe a situation where a chemical change has occurred? Check all that apply.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

• The baking soda and hydrochloric acid combined, and bubbles formed. 

• The baking soda absorbed the hydrochloric acid. 

• Some of the baking soda dissolved in the hydochloric acid.

• The hydrochloric acid evaporated, leaving only the baking soda. 

Tags

NGSS.MS-PS1-2

What key words, when present in a question about chemical reactions, might indicate a chemical change is occuring? Check all that apply.

• Bubbling

• Fizzing

• Dissolving

• Evaporating

Tags

NGSS.MS-PS1-2

• One of the original compounds came out of solution

• The solutions reacted chemically

• Some of the water froze into ice crystals

• Rapid evaporation of water occured, leaving a solid

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

Which of the following does NOT indicate a chemical reaction is occuring? Check all that apply.

• Unknown A dissolves into Unknown B

• Unknown A creates fizzing and bubbles when combined with Unknown B

• Unknown A sinks to the bottom when added to Unknown B

• Unknown A floats to the top when added to Unknown B

Tags

NGSS.MS-PS1-2

Which scientific observation, shown in the chart, indicates that a chemical reaction has NOT occurred?

• Number 1

• Number 2

• Number 3

• Number 4

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

• The shape of the coal changes

• Oxygen is present

• A new substance is produced

• Coal is made up of more than one element

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

• A gas is present

• The total number of atoms remains unchanged

• The state of matter remains the same

• A brown gas is produced

Tags

NGSS.MS-PS1-2

A solid piece of chocolate is melted and changed to liquid form. Which property of the piece of chocolate will remain the same?

• Texture
• Temperature
  
• Shape
•  Mass

Tags

NGSS.MS-PS1-4

NGSS.MS-PS1-5

Which of the following is NOT an example of a physical change?

• crumpled paper
• pencil sharpening
• shrunken clothing
• rust