Density / Mixtures and Solutions Review

Fourth graders have created a mixture that includes pebbles, salt, and water. What tools do the students need to take to separate this mixture?

• a coffee filter and condensation

• a magnet wand and coffee filter

• a magnet wand and evaporation

• a filter and evaporation

Students are at a sandy lake looking for pebbles to skip across the water. What would be the fastest way to help them separate the pebbles from the sand?

• sieve

• magnet

• coffee filter

• none of these

What method is the best to separate a mixture of small shells and water?

• magnetism

• filtration

• evaporation

What method is the best to separate a mixture of sugar and water?

• magnetism

• filtration

• evaporation

What method is the best to separate a mixture of paper clips and sand?

• magnetism

• filtration

• evaporation

What method is the best to separate a mixture of sand and water?

• magnetism

• filtration

• evaporation

An equal amount of peanuts, sunflower seeds, pretzels, and M&Ms are being mixed for trail mix. Which statement is NOT true about this mixture?

• The physical properties of these solids have not changed.

• The mixture can be separated best by evaporation.

• The substances can be easily separated.

• The parts of this mixture have not dissolved.

For a science lab, students mixed equal parts water and salt. This salt water made a solution because -

• each ingredient did not change.

• the ingredients are evenly distributed and one substance dissolved into another.

• The substances can be easily separated.

• the ingredients are evenly distributed and did not dissolve.

Tags

NGSS.MS-PS1-2

In the science lab, students separated a mystery mixture by using two methods.

First, by using a sieve to separate the larger particles from the smaller particles.

Second, by using a magnet wand to separate the last two parts.

Which materials could they have been separating?

• shampoo

  syrup

  water

• sunflower seeds

  peanuts

  sugar

• colored beads

  dice

  pennies

• pebbles

  salt

  iron filings

All of the following are mixtures EXCEPT -

• popcorn,

  M&Ms, and

  pretzel sticks

• steel nails and

  pebbles

• sand and hot water

• chocolate powder and milk