Chemistry Mixtures

Mixtures: A Science Study

PDF version: Mixtures A Science Unit

Access your background knowledge:

    1. What is everything – all matter, all substances – made of?
    2. What is the difference between an atom and a molecule?
    3. What is the difference between physical and chemical change?
    4. What is the difference between a compound and a mixture?
    5. What is density?

Record your background knowledge using one or more of these methods:

    1. write sentence answers to the questions above (fully meeting expectations)
    2. add little coloured diagrams to help explain your answers (exceeding)

Read:

  1. Your science text – Nelson Science: Chemistry: Mixtures – page 58 – 111. (meeting)
  2. At least 2 nonfiction books about chemistry. (exceeding)

Record your new knowledge:

    1. Copy the diagram on page 62. (meeting expectations)
      1. add coloured illustrations (fully meeting)
      2. add 3 examples to each column (exceeding)
    2. Make a diagram of four types of colloids (p. 72 -75). (meeting)
      1. add coloured illustrations (fully meeting)
      2. add 3 examples to each column (exceeding)
    3. Make a diagram of seven ways to separate mixtures: p. 100-101. (meeting ex.)
      1. add coloured illustrations (fully meeting)
      2. add at least one real-life example for each method (exceeding)
    4. Make a diagram showing five reasons indigenous people separated mixtures.
      1. add coloured illustrations (fully meeting)
      2. add at least one real-life example for each reason (exceeding)
    5. Make a diagram showing five ways mixtures are filtered in nature: p. 84-85.
      1. add coloured illustrations (fully meeting)
      2. add at least one real-life example for each method (exceeding)

Do at least 2 experiments:

  • Use light to decide if a liquid is a homogeneous or heterogeneous mixture: p. 67.
    • complete the attached worksheet (meeting)
    • write out the whole completed worksheet yourself (fully meeting)
    • write out the experiment and add coloured illustrations (exceeding)
  • Mix oil and water and add an emulsifier: p. 72.
    • complete the attached worksheet (meeting)
    • write out the whole completed worksheet yourself (fully meeting)
    • write out the experiment and add coloured illustrations (exceeding)
  • Make a gel: p. 74.
    • notes of your results (minimally meeting)
    • a lab write-up: hypothesis, materials, procedure, observations, results (fully)
    • a lab write-up with illustrations (exceeding)
  • Make a foam: p. 76-77.
    • notes of your results (minimally meeting)
    • a lab write-up: hypothesis, materials, procedure, observations, results (fully)
    • a lab write-up with illustrations (exceeding)
  • Use centrifuge to separate chocolate milk: p. 93.
    • notes of your results (minimally meeting)
    • a lab write-up: hypothesis, materials, procedure, observations, results (fully)
    • a lab write-up with illustrations (exceeding)
  • Separate a mixture using magnetism: p. 96.
    • notes of your results (minimally meeting)
    • a lab write-up: hypothesis, materials, procedure, observations, results (fully)
    • a lab write-up with illustrations (exceeding)
  • Separate a mixture using chromatography: p. 99.
    • notes of your results (minimally meeting)
    • a lab write-up: hypothesis, materials, procedure, observations, results (fully)
    • a lab write-up with illustrations (exceeding)
  • Make a dye: p. 104-105.
    • notes of your results (minimally meeting)
    • a lab write-up: hypothesis, materials, procedure, observations, results (fully)
    • a lab write-up with illustrations (exceeding)

Do some research by completing one of the following projects:

    1. Make an illustrated diagram of substances in your kitchen at home:
      1. homogeneous solutions
      2. heterogeneous mixtures
      3. compounds
    2. Make an illustrated diagram of heterogeneous mixtures in your home:
      1. suspensions
      2. colloids: foams, emulsions, gels, sols

Review your knowledge by completing these sentences:

  1. There are about ______ pure substances on earth. An _____________ is a type of substance created from atoms. All of these ______________ are arranged on a _____________ table.
  2. An ________ is the smallest part of an ____________. It contains ____________ , ____________ , and ______________ .
  3. A _______________ is formed when two or more __________ join together. They can be of the same element or of ___________ elements.
  4. A _____________ is formed when two or more elements make a chemical bond and create a new substance. An example is water, which is made from two ___________ atoms and one __________ atom.
  5. A _____________ is created when two or more elements combine but do not make a new chemical substance. An example is muddy water, which combines soil and water.
  6. A _____________ is when one substance is dissolved into another substance. The substance that dissolved is called a _____________ . The substance that does the dissolving is called a _____________ . An example is salt water, in which the salt is a _________ and the water is a _____________ . Light _________through these mixtures.
  7. A ______________ is a heterogeneous mixture in which the particles form __________ over time. An example is oil and vinegar, which can be shaken to form a mixture but then will __________ after awhile. Light is ____________ by these mixtures.
  8. A ____________ is a heterogeneous mixture that does not settle into layers. An example is popcorn, which is a _______ in a solid. Another example is a gel, which is a __________ in a solid. Still another example is fog, which is __________ suspended in _________.
  9. Some substances are good at creating colloids. These substances are called _______________. An example is ________ gum in salad dressing, which prevents the oil and vinegar from _________________ .

100                  air                    atom                atoms              colloid             compound

different          electrons         element           element           elements         emulsifiers     

gas                  hydrogen         layers              liquid               oxygen             mixture

molecule         neutrons          periodic           protons            scattered         separate

separating       solute              solute              solution           solvent            solvent

suspension      travels             xanthum          water

 

  1. ________________ can be separated in many different ways.

 

  1. _____________________ is a way to separate pigments – or colours – from liquid.

 

  1. _________________ separates solid substances from liquids such as water.

 

  1. ______________ uses a filter to separate larger ________________ from liquids or smaller particles.

 

  1. _________________ separates mixtures by adding water and letting the lighter _____________ float to the top.

 

  1. ______________ separates solid particles from other particles using a magnet. This is used in the mining industry to separate rocks with _________ from other rocks.

 

  1. ________________ separates solid parts – or even liquid particles – by the process of spinning. It is used in hospitals to separate ___________ and in homes to get the water out of ____________ in washing machines.

 

  1. ___________________ is often used by just about everyone. It is simply using one’s fingers to separate mixtures.

blood               centrifugation             chromatography          clothes            filtration

flotation          iron                              magnetism                  mixtures          particles

particles          picking apart               settling

 

 

Suspension, Colloid, or Solution?

Hypothesis: Suspensions have particles that separate into layers over time. Colloids and solutions to do not separate into layers. Light is scattered by suspensions and colloids but not by solutions, so I should be able to distinguish between the two types of mixtures by looking at them and shining a light on them.

 

Materials: clear jar, water, teaspoon, milk, flashlight

Procedure:

  1. Fill a 250 ml jar with water.
  2. Shine a light on it and notice the effect on the light.
  3. Add 2 teaspoons of milk and stir.
  4. Notice the appearance of the milky water.
  5. Shine a light on it and notice the effect on the light.

 

Results: The water without milk allowed the light to ______________________ . The water with milk ______________________________________ . I watched the milk for _____ min. and observed that ___________________________________ .

 

Conclusion: Milk is a ____________________ rather than a __________________  or a ________________________.

Now I will do the experiment again with other liquids, testing to see if they are solutions or suspensions.

 

Can I Make a Colloid?

Hypothesis: Some substances allow two liquids that quickly separate into layers to be emulsified so that the particles stay suspended and do not separate.

Materials: clear jar, vinegar, oil, teaspoon, flashlight, xanthum gum

Procedure:

  1. Fill the jar with 1 cm of oil.
  2. Carefully add 2 cm of vinegar.
  3. Observe what happens.
  4. Shine a flashlight on the mixture and observe.
  5. Add ½ tsp of xanthum gum and stir.
  6. Observe what happens.
  7. Shine a flashlight on the mixture and observe.

Results: The oil and vinegar allowed the light to ____________________ even though the two substances did not form a ______________________ mixture. The _____ was on top because its molecules are larger and cannot pack together as closely as the molecules in v_____________ (C2H4O2). The xanthum gum caused the two substances to e______________ so that the particles of oil can be suspended throughout the vinegar.

Print Friendly, PDF & Email