Physical Science Study Guide (S5P1, P2, P3)

Front

In which investigation did the student observe a chemical change?

Back

Investigation 2, because a new substance was formed. The combination of the acetic acid and baking soda resulted in a gas being formed and released. This is evidence of a chemical change.

Answer explanation

When acetic acid (like vinegar) and baking soda are mixed, they react to make a gas that bubbles up and escapes. This shows that a chemical change happened.

Front

How can Tony change the paper in a way that is unable to be reversed?

Back

burn the paper

Front

Which action in Rosa's list is NOT a physical change? - tearing lettuce - cutting tomatoes - boiling an egg - stirring oil and vinegar

Back

boiling an egg because the end result cannot be reversed

Answer explanation

A physical change is when something changes in a way that doesn’t make a new substance. It just changes its appearance or form. For example, if you break a pencil or melt ice into water, the pencil is still a pencil and the water is still water — they just look different. No new substances are made, so it's a physical change!

Front

What method of separating a mixture of water, sugar, and sand would remove the sand, but still leave the sugar and water in the beaker?

Back

using a filter

Answer explanation

If you have a mixture of sand, sugar, and water, the sand is bigger and can't dissolve in water, while sugar can dissolve. To separate the sand, you can use a filter. A filter is like a net that lets the small things, like water and dissolved sugar, pass through, but it traps the bigger pieces, like sand.

So, when you pour the mixture through the filter, the sand will get caught in the filter, and the sugar and water will go through into the beaker. This way, you'll remove the sand but still keep the sugar and water!

Front

Two students have identical beakers with 50 mL of liquid water. Student 1 places his beaker in the freezer. Student 2 places her beaker over a burner. The students both agree that temperature will be responsible for changing the state of their liquid water samples. Which argument BEST supports the students' claim?

Back

Student 1’s water will become a solid because losing heat causes the particles in the water to slow down. Student 2’s water will become a gas because adding heat causes the particles in the water to speed up.

Front

Which nail provides evidence of a chemical change?

Back

Nail 3 provides evidence of a chemical change because there is a change in color. The change of color indicates that rust is forming which is a chemical change because it cannot be reversed.

Front

Where should students note the color change from blue to yellow in a laboratory report?

Back

under "Observations"

Front

Which material provides evidence of a chemical change when heat is applied?

Back

The piece of paper because a new substance is formed. The paper combines with oxygen and forms ashes and smoke, which is not a reversible process.

Front

A student is planning an investigation for her science project using a single sample of water. She will record the observable properties of the water at room temperature, when heat is added, and when heat is removed. Which statement best describes the investigation?

Back

The student is planning to demonstrate a physical change because the water may undergo changes in its state but its chemical makeup will not change.

Answer explanation

The student is showing a physical change because the water is just changing how it looks or feels, not what it is made of.

Front

Pete stirs together two cups of flour and one cup of rice in the same bowl. Which process would BEST provide evidence that the flour and rice have only experienced a physical change?

Back

Sifting the contents of the bowl so that the flour and rice become separate again.