Mechanical Mixtures

Hey Seniantha and Jayren, can you figure out what a mixture is?

• A combination of two or more substances that are chemically combined

• A combination of two or more substances that are physically combined and retain their chemical identity

• A single substance made of identical molecules

• A chemical reaction between two substances

Answer explanation

A mixture is defined as a combination of two or more substances that are physically combined, meaning they retain their individual chemical identities. This distinguishes it from a compound, where substances are chemically combined.

Riley and Jordan are mixing things in the kitchen. Which of the following mixtures will look the same throughout?

• Oil and water

• Salt and sand

• Vinegar and water

• Salad with dressing

Answer explanation

Vinegar and water form a homogenous mixture because they mix uniformly at the molecular level, creating a solution. In contrast, oil and water, salt and sand, and salad with dressing are not uniform mixtures.

Imagine Keland and Jessa are exploring mixtures in science class. Keland says, "You can't see the individual components in a (a)   mixture, but you can in a heterogeneous mixture!"

• Homogenous mixtures have only one s

• You cannot see the individual compo

• Homogenous mixtures are always liqu

• Homogenous mixtures are chemical re

Answer explanation

In a homogenous mixture, the components are evenly distributed and not visible, while in a heterogenous mixture, the individual components can be seen and are not uniformly mixed.

Cartier and Jordan are mixing things in the science lab. Which of the following mixtures did they create that is a heterogenous mixture?

• Salt dissolved in water

• Sugar dissolved in tea

• Sand and salt mixed together

• Vinegar and water mixed together

Answer explanation

A heterogeneous mixture consists of visibly different substances. Sand and salt mixed together retain their individual properties, making it a heterogeneous mixture, unlike the other options which are homogeneous.

Hey science whizzes! Farrah and Lee are in a friendly debate. Can you help them out? What two metals make up the shiny, musical alloy known as brass?

• Copper and tin

• Copper and zinc

• Zinc and iron

• Aluminum and copper

Answer explanation

Brass is an alloy primarily composed of copper and zinc. The other options listed do not accurately represent the metals that make up brass.

Cruz and Riley are having a fizzy drink debate! Can you help them settle it? Which statement is true about soft drinks?

• They are a mixture of only liquids

• They are a mixture of gases only

• They are a mixture of solids, liquids, and gases

• They are a solid homogenous mixture

Answer explanation

Soft drinks contain dissolved solids (like sugars), liquids (the beverage itself), and gases (carbonation). Therefore, the correct statement is that they are a mixture of solids, liquids, and gases.

Match the following mixtures with their types.

• Homogeneous mixture of salt and water

• Air

• Homogeneous mixture of gases

• Asphalt

• Homogeneous mixture of sugar and water

• Sugar water

• Mechanical mixture of aggregates and binder

• Saltwater

Answer explanation

Asphalt is a mechanical mixture because it consists of different materials (aggregates and bitumen) that retain their individual properties. In contrast, saltwater, air, and sugar water are solutions where components are dissolved or uniformly mixed.

Imagine Ryan and Kale are on a science adventure! They discover that air is an example of which type of mixture?

• A homogenous mixture of solids

• A heterogenous mixture of gases

• A homogenous mixture of gases

• A heterogenous mixture of solids, liquids, and gases

Answer explanation

Air is a homogenous mixture of gases, meaning its composition is uniform throughout. Unlike heterogeneous mixtures, the gases in air (like nitrogen and oxygen) are evenly distributed, making it a homogenous mixture.

Natannah and Dheniel are making a salad with oil and vinegar dressing. Can you help them figure out what type of mixture their dressing is?

• Homogenous

• Heterogenous

• Solution

• Pure substance

Answer explanation

The dressing in a salad with oil and vinegar is classified as a heterogenous mixture because the oil and vinegar do not fully combine, allowing distinct layers to be seen, unlike a homogenous mixture where components are uniformly distributed.

Lambert and Violet are on a quest to discover why asphalt is considered a mechanical mixture. Can you help them figure it out?

• Because you cannot see the individual components

• Because the components chemically combine

• Because the components retain their individual properties and are visible

• Because it is a liquid mixture of water and gravel

Answer explanation

Asphalt is a mechanical mixture because its components, like aggregates and bitumen, retain their individual properties and can be seen separately, unlike a chemical mixture where components combine chemically.