Changes in Matter

Multiple Choice

What do you predict will happen to the mass of the nails after they rust, if none of the rust falls off?

• The mass of the dry, rusted nails will be more than the mass of the dry nails before they rusted.

• The mass of the dry, rusted nails will be less than the mass of the dry nails before they rusted.

• The mass of the dry, rusted nails will be the same as the mass of the dry nails before they rusted.

Multiple Choice

What are the two main types of changes that matter can undergo?

• Physical and chemical changes

• Solid and liquid changes

• Melting and freezing changes

• Evaporation and condensation changes

Multiple Choice

Explain the difference between a physical change and a chemical change using examples from the slides.

• A physical change is reversible (e.g., boiling water), while a chemical change is always irreversible (e.g., digesting food).
• A physical change involves chemical reactions (e.g., baking bread), while a chemical change does not (e.g., dissolving sugar).
• A physical change alters appearance without changing composition (e.g., melting ice), while a chemical change creates new substances (e.g., rusting iron).
• A physical change creates new substances (e.g., burning wood), while a chemical change alters appearance (e.g., freezing water).

Multiple Choice

List three questions you can ask yourself to determine if a change is physical, based on the slides.

• Does the change affect the color of the substance?
• Is the change permanent or temporary?
• Is the temperature of the substance altered?
• 1. Is the substance still the same after the change? 2. Can the change be reversed? 3. Does the change involve a change in state?

Multiple Select

Which of the following are examples of physical changes?

• Melting an ice cube

• Burning wood

• Mixing sand with water

• Boiling water

Multiple Choice

Which of the following best describes a chemical change, as shown in the transformation of wood to ash?

• Matter changes state but remains the same substance

• Matter is broken into smaller pieces but remains the same

• Matter becomes something completely new and new matter is formed

• Matter is mixed but can be separated again

Multiple Choice

Explain how a chemical reaction leads to the formation of new substances, using the example of methane and oxygen reacting.

• The reaction produces glucose and ethylene as new substances.
• The reaction of methane and oxygen produces carbon dioxide and water.
• Methane and oxygen combine to form sulfur dioxide and ammonia.
• The reaction of methane and oxygen creates nitrogen and hydrogen.

Multiple Choice

Which of the following are signs that a chemical change has occurred?

• Unexpected color change

• Unexpected temperature change

• Burning

• All of the above

Multiple Select

Select all examples that represent a chemical change from the list below.

• Iron rusting

• Burning wood

• Cooking an egg

• Melting ice

Multiple Choice

Compare and contrast rusting, tarnishing, and oxidation as chemical changes involving metals. What do they have in common and how are they different?

• Rusting is a type of oxidation, tarnishing is a form of rusting, and oxidation only happens in non-metals.
• Rusting is specific to iron, tarnishing affects silver, and oxidation is a general term for electron loss, often involving oxygen.
• Rusting occurs in all metals, tarnishing is only for gold, and oxidation is a process of gaining electrons.
• Rusting affects copper, tarnishing is related to aluminum, and oxidation is a process of color change.

Multiple Choice

Which process caused the Statue of Liberty to change color over time?

• Oxidation

• Melting

• Evaporation

• Condensation

Multiple Choice

Explain why rust, tarnish, or oxidation cannot be reversed to get back the original air and water.

• Rust, tarnish, or oxidation cannot be reversed to get back the original air and water because they involve irreversible chemical changes.
• Chemical changes can always be undone with heat.
• Oxidation can be reversed by adding more oxygen.
• Rust and tarnish can be easily cleaned with soap.

Multiple Select

Which of the following are evidence of a chemical change?

• Smoke or fire

• Heat or light

• Fizzing/bubbles

• All of the above

Multiple Choice

Describe how baking cookies is an example of a chemical change.

• Baking cookies is a physical change as it only alters the shape of the dough.
• Baking cookies involves no chemical reactions and keeps the ingredients unchanged.
• Baking cookies is a process that only affects the texture of the ingredients.
• Baking cookies is a chemical change because it transforms the raw ingredients into a new product through chemical reactions.

Multiple Choice

Select the statement that is the best comparison of the total mass of the jar and its contents before and after the seeds sprouted to form seedlings:

• The total mass of the original jar with seeds will be more than the total mass of the jar with the seedlings.

• The total mass of the original jar with seeds will be less than the total mass of the jar with the seedlings.

• There will be no change in the total mass of the jar with seedlings after 12 days.