Formation of a New Substance

Which of the following situations provides evidence that a chemical change has taken place?

• Water, when boiled, evaporates and turns into vapor.

• Sugar, when added to iced tea, dissolves into the liquid.

• Two liquids are mixed, and a new solid substance (a precipitate) forms.

• A piece of paper is cut into many small pieces.

Tags

NGSS.MS-PS1-2

Which of the following would indicate the formation of a new substance?

• A liquid turns to a solid

• A sample of metal melts

• Bubbles and fizzing occur

• A solid dissolves in a liquid

Tags

NGSS.MS-PS1-2

Which is an example of a different substance being formed?

• glass breaking

• metal melting

• water freezing

• wood burning

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A chemical change always results in the formation of a:

• explosion

• big mess

• new substance

• new state of matter

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A company that makes frying pans needs to create a new substance to coat the pans. The substance must have a high melting point. To create this new substance, workers mixed together two substances that melt at low temperatures in a sealed container. The diagram above shows the repeating groups of atoms that make up the two starting substances.

After mixing, the workers found two substances that melt at higher temperatures in the sealed container. (Nothing had escaped.) Which of the diagrams to the left shows the repeating groups of atoms that make up the ending substances?

• 
• A

• B

• C

• D

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The question on the test says: "Explain if the model correctly shows why a chemical reaction can result in a molecule with different properties."

The student wrote: "This is not a correct model because we have hydrogen (H) and oxygen (O) on one side but water (H₂0) on the other side."

Is the student correct?

• Correct, atoms cannot be rearranged to form new molecules

• Incorrect, during a chemical reaction, atoms are rearranged and can form new molecules

• Incorrect, the H and O atoms are destroyed. Then H₂O atoms are created.

• Incorrect, two gases cannot create a liquid during a chemical reaction.

Tags

NGSS.MS-PS1-2

Which processes above can be used as evidence to identify the formation of a new substance?

• Processes A, B, C, and D

• Processes B, C, E, and F

• Processes B, C, D, and F

• Processes C, D, E, and F

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Substances were mixed with a clear liquid. Based on the observations on the chart, for which mixture is there the best evidence that a new substance was formed?

• Substance 1

• Substance 2

• Substance 3

• Substance 4

Tags

NGSS.MS-PS1-2

The table records the observations that result from four different combinations. Which combination of substances shows evidence that a new substance was formed?

• Combination of oil and water

• Combination of salt and water

• Combination of baking soda and vinegar

• Combination of iron filings and sand

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which is the best example of a new substance forming?

• lighting a match

• cutting a piece of paper

• popping a balloon

• hitting a nail with a hammer

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5