Question

lesson review

1. which of these is not made up of two or more substances that are combined physically?

a. homogeneous mixture
b. compound
c. heterogeneous mixture
d. solution

1. an unknown substance is provided in a science class. looking at the substance, a student observes different colors and different sizes of particles unevenly distributed throughout the substance. what type of substance is this?

a. solution
b. compound
c. heterogeneous mixture
d. homogeneous mixture

1. filtration can be used to separate a mixture of

a. a solid and a liquid.
b. a liquid and a gas.
c. two liquids.
d. two solids.

1. which of these processes would be useful for separating a dissolved solid from a liquid?

a. evaporation
b. filtration
c. sifting
d. mixing

Explanation:

Question 1

To solve this, we analyze each option:

• A homogeneous mixture (A) is a physical combination of substances (e.g., salt water).
• A compound (B) is a chemical combination of elements, not a physical mixture of substances.
• A heterogeneous mixture (C) is a physical combination (e.g., salad).
• A solution (D) is a type of homogeneous mixture, so it’s a physical combination.

So the one not made of physically combined substances is a compound.

Analyze the observations: different colors, particle sizes, and uneven distribution.

• A solution (A) is homogeneous (uniform).
• A compound (B) is chemically combined, not a mixture.
• A heterogeneous mixture (C) has non - uniform composition (uneven particle distribution, different colors/sizes match this).
• A homogeneous mixture (D) is uniform.

So the substance is a heterogeneous mixture.

Filtration works by passing a mixture through a filter.

• A solid and a liquid (A): The filter traps the solid, allowing the liquid to pass (e.g., sand and water).
• A liquid and a gas (B): Filtration isn't used for this (e.g., air and water vapor).
• Two liquids (C): Filtration can't separate them (e.g., oil and water; we use separation funnels).
• Two solids (D): Filtration is for solid - liquid, not solid - solid.

So filtration separates a solid and a liquid.

Answer:

B. compound

Question 2