TEST IN SCIENCE 6 1ST QUARTER

What best describes a suspension?

• A homogenous mixture of two or more materials.

• A chemical reaction between two substances.

• A mixture where substances are uniformly dispersed.

• A heterogeneous mixture where particles settle out over time.

How do suspensions differ from solutions?

• Suspensions cannot be stirred, while solution can.

• Suspensions are uniformly dissolved, while solutions have particles that settle out over time.

• Suspensions are always transparent, while solutions are opaque.

• Suspensions involve particles that can be separated by filtration, while solutions do not.

Which of the following mixtures is an example of a suspension?

• salt dissolved in water

• syrup

• air in the atmosphere

• flour dissolved in water

What happens to the particles of a suspension when left untouched?

• Particles become lighter.

• Particles will evaporate into the air.

• Particles settle at the bottom of the container.

• Particles will dissolve in the solvent.

What process of separating mixtures is commonly used to separate the components of a suspension?

• evaporation

• distillation

• filtration

• winnowing

Which description best describes colloids?

• Composed of molecules larger than a solution but smaller than a suspension.

• Combination of two or more substances that can be easily separated.

• Have molecules that are big enough to settle at the bottom.

• Formed by mixing different kinds of solutions.

Which of the following is the best description of colloids?

• clear, flawless substance

• clear, pure substance

• dark, black substance

• sticky, creamy substance

Which colloid has both protective and decorative purposes?

• ink

• paint

• insecticide spray

• creams

Oil and water do not mix uniformly. How can we separate this mixture?

• chromatography

• decantation

• centrifugation

• filtration

What technique is used to separate salt from seawater through exposure to heat or sun?

• decantation

• evaporation

• filtration

• sedimentation