Chemical Reactions

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NGSS.MS-PS1-2

NGSS.MS-PS1-5

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NGSS.MS-PS1-5

What is the difference between a physical and chemical change?

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NGSS.MS-PS1-4

A scientist spilled a few drops of dilute hydrochloric acid (HCl) on a lab table. For safety purposes, the scientist sprinkled some baking soda into the spill. Which observation would provide the best evidence that a chemical reaction occurred?

• 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 hydrochloric acid.

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

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NGSS.MS-PS1-2

A chemist added by hydrochloric acid to a sample of baking soda in a beaker. Immediately, the mixture of the two chemicals began to fizz and bubble. Which of the following observations about the fizzing mixture provides evidence of a chemical reaction?

• The temperature of the beaker did not change.

• A substance escaped from the beaker in the form of a gas.

• Most of the baking soda appeared to dissolve in the acid.

• Some of the baking soda remained in the bottom of the beaker.

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NGSS.MS-PS1-2

Annelise conducted an experiment by applying heat to aluminum, paper, water and wax. The results to her experiment are shown in the table above.

Which substance went through a chemical reaction?

• water

• aluminum

• wax

• paper

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NGSS.MS-PS1-2

Iron fillings are added to copper sulfate solution. Use the diagram to answer any questions that follow. Which of the following does NOT indicate that a chemical reaction occurred when the iron fillings were added to the copper sulfate.

• The final solution formed bubbles.

• The volume of the solution increased.

• The color of the solution changed.

• The temperature increased.

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NGSS.MS-PS1-2

Does the following chemical equation follow the Law of Conservation of Mass?

• yes

• no

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NGSS.MS-PS1-5

The equation below represents a chemical reaction in living cells.

C₆H₁₂O₆ + 6O₂ = 6CO₂ + 6H₂O + energy

How many atoms are represented in the reactants of this equation?

• 6

• 12

• 24

• 36

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NGSS.MS-PS1-1

NGSS.MS-PS1-5

Coal contains carbon and other elements. Carbon dioxide forms when coal burns in the presence of oxygen. Which of these is the best evidence that a chemical reaction occurs when coal burns?

• 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