A paragraph describing the difference between a physical and a chemical change.

Answer 1

A physical change refers to a transformation that alters the form or appearance of a substance without changing its chemical composition. Examples of physical changes include melting, freezing, and dissolving, where the material remains the same at a molecular level despite variations in state or shape. Conversely, a chemical change involves a process that transforms one substance into another through a chemical reaction, resulting in the formation of new substances with different properties. This can be observed in processes such as combustion, rusting, or digestion, where the original materials undergo a fundamental change in their molecular structure. In summary, physical changes are reversible and do not affect the substance's identity, while chemical changes are often irreversible and produce new materials.

Answer 2

Make a table or chart and list 5 physical changes and 5 chemical changes.

Answer 3

Here is a table listing 5 examples of physical changes and 5 examples of chemical changes:

| Type of Change | Examples | |-------------------------|-----------------------------------------| | Physical Changes | 1. Melting of ice | | | 2. Boiling water | | | 3. Dissolving sugar in water | | | 4. Cutting paper | | | 5. Chopping wood | |-------------------------|-----------------------------------------| | Chemical Changes | 1. Burning wood | | | 2. Iron rusting | | | 3. Baking a cake | | | 4. Reacting vinegar with baking soda | | | 5. Fermentation of grapes |

This table highlights clear examples of both physical and chemical changes, showcasing their distinct characteristics.

Answer 4

Perform a simple action/experiment and explain whether the experiment was a physical or chemical change.
Include beginning observations, ending observations and an explanation of whether it was a physical or chemical change and how you know.
This could be as simple as ripping a piece of paper in half, lighting a candle/match, creating a mixture of sand and rocks, baking cookies, mixing baking soda and vinegar, adding vinegar to milk, rolling out playdough, cutting an apple, cooking an egg, or anything else.

Answer 5

Experiment: Mixing Baking Soda and Vinegar

Beginning Observations:

• Materials: I have a small bowl of baking soda (white powder) and a small bowl of vinegar (clear liquid).
• The baking soda looks like a fine white powder and has no distinct smell. The vinegar has a sharp, tangy smell and is a clear liquid.
• I place about two tablespoons of baking soda in the bowl and prepare to pour in the vinegar.

Action:

1. I pour the vinegar into the bowl containing the baking soda.

Ending Observations:

• Upon mixing, a vigorous fizzing and bubbling action occurs as the two substances react. The bubbles are rapidly produced and rise to the surface, creating foam that eventually overflows from the bowl.
• The initial white powder of baking soda is no longer visible. Instead, there is a cloudy foam and gas escaping, which has a slight vinegar smell.

Analysis: This experiment demonstrates a chemical change. The reaction between baking soda (sodium bicarbonate) and vinegar (acetic acid) produces carbon dioxide gas, which causes the fizzing and bubbling observed.

How I Know:

1. New Substances Formed: The mixture produces carbon dioxide gas, which is evident through the bubbles and fizzing. The reaction also results in water and sodium acetate (a new substance), indicating a chemical transformation.
2. Irreversibility: The production of gas and the reaction cannot be reversed by simply mixing the original substances back together, further supporting that a chemical change has occurred.
3. Change in Properties: The mixture's physical properties, such as texture and smell, changed significantly as the baking soda and vinegar reacted, indicating that the identity of the original substances has changed.

Overall, this experiment effectively illustrates a chemical change due to the formation of new substances, observable gas production, and a change in properties.