TEKS 5.6BC Science

A student makes a mixture of gravel, iron filings, and water. Which table correctly identifies the tools that can be used to separate each substance from the mixture?

• Screen - Gravel, Magnet - Iron filings, Paper filter - Water

• Funnel - Gravel, Paper filter - Iron filings, Hot plate - Water

• Screen - Gravel, Hot Plate - Iron filings, Funnel - Water

• Paper filter - Gravel, Magnet - Iron filings, Screen - Water

Answer explanation

The correct choice is 'Screen - Gravel, Magnet - Iron filings, Paper filter - Water' because a screen separates larger particles like gravel, a magnet attracts iron filings, and a paper filter separates water from solids.

Which mixture is paired with the best tool for separating the materials?

• Mixture: Salt and pepper, Tool: Tweezers

• Mixture: Pieces of cork and pebbles, Tool: Beaker of water

• Mixture: Safety pins and iron nails, Tool: Magnet

• Mixture: Sand and iron filings, Tool: Colander

Answer explanation

The best tool for separating pieces of cork and pebbles is a beaker of water, as cork floats while pebbles sink, allowing for easy separation. Other options do not effectively separate the given mixtures.

The students are trying to determine the presence of which substance in the cereal?

• Sugar

• Iron

• Salt

• Wheat

Answer explanation

The students are testing for iron because many cereals are fortified with this nutrient to help prevent iron deficiency. Sugar, salt, and wheat are common ingredients but not specifically tested for in this context.

Which statement is true about the mixture?

• The mass of the mixture is 85 grams.

• The mass of the mixture is 60 milliliters.

• The volume of the mixture is 60 grams.

• The volume of the mixture is 85 milliliters.

Answer explanation

The correct statement is that the mass of the mixture is 85 grams. Mass is measured in grams, while volume is measured in milliliters. The other options incorrectly mix these units.

In which mixtures do all the ingredients maintain their physical state?

• Mixtures 3 and 4 only

• Mixtures 1, 3, and 4

• Mixtures 1, 2, and 5

• Mixtures 2 and 5 only

Answer explanation

Mixtures 3 and 4 maintain the physical state of all ingredients, meaning no chemical changes occur. Mixtures 1, 2, and 5 involve changes that alter the state of at least one ingredient, making them incorrect choices.

A student heats 250 milliliters of water in a cup to approximately 50°C and adds 6 grams of salt. The mixture of salt and water is then stirred for 15 seconds. Which results will the student MOST LIKELY observe after the mixture has been stirred for 15 seconds? Select TWO correct answers.

• The salt will dissolve.

• The salt will sink to the bottom of the cup.

• The water will remain clear.

• The salt will float on the water.

• The water will change from clear to opaque white.

Answer explanation

The salt will dissolve in the warm water, creating a clear solution. The water will remain clear as the dissolved salt does not change its color or opacity.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

Which change most likely occurs to the sugar when it is added to the water?

• The sugar breaks down to form a new substance in the solution.

• The sugar changes water into a new substance in the solution.

• The sugar floats on the surface of the water in the solution.

• The sugar completely dissolves in the solution.

Answer explanation

When sugar is added to water, it dissolves, meaning it breaks down into smaller particles that mix uniformly with the water, creating a solution. This is why the correct answer is that the sugar completely dissolves in the solution.

Tags

NGSS.MS-PS1-2

What most likely happened to the sugar in the mixture?

• The sugar evaporated at the lower temperature in the refrigerator without causing any changes to the fruit and nuts.

• The sugar was more dense than the other foods in the mixture, so it settled to the bottom of the container.

• The sugar dissolved in the moisture on the fruit.

• The sugar absorbed energy from the nuts and melted into a colorless liquid.

Answer explanation

The sugar likely dissolved in the moisture on the fruit, creating a sweet solution that enhances the flavor, rather than evaporating or settling, which would not effectively mix with the other ingredients.

Tags

NGSS.MS-PS1-2

Which change occurs when lemon juice is mixed with water?

• The mass of the lemon juice decreases.

• The water becomes a solid.

• The lemon juice dissolves and spreads out evenly in the water.

• The volume of the water decreases.

Answer explanation

When lemon juice is mixed with water, it dissolves, meaning the lemon juice spreads out evenly throughout the water, creating a uniform solution. This is the correct change that occurs.

Tags

NGSS.MS-PS1-2

Which property will the sugar keep after it has dissolved in the water?

• Its grainy texture

• Its whitish color

• Its temperature

• Its sweetness

Answer explanation

When sugar dissolves in water, it retains its sweetness. The grainy texture and whitish color disappear, and the temperature of the solution may change, but the sweet taste remains unchanged.