In this inquiry, students will be shown how to make ice cream.  They will, using scaffolded handouts from Smarter Science Canada, select one variable to modify to increase the amount of heat transfer that happens between the cream and the ice/salt mixture.  They will choose an independent variable to change out of a brainstormed list.  Students will then pick one variable to test.  Students will be given the dependent variable (how fast the temperature of the cream mixture drops or time taken to get the cream to a certain temperature). If students are not familiar with the scientific process, they can do a pair of skill builders (penny drop and floating candles), followed by demonstrations and a literacy connection about the science of ice cream. After the main inquiry of making ice cream, the teacher may choose an extension inquiry on another physical property, the M&M Solubility Inquiry.

Grade Level/Course Code: Grade 9 Applied Science, SNC1P

Strand(s) and Unit(s): Chemistry

Inquiry Focus:

Key question:  How do I change a variable to increase how fast the cream forms into ice cream?

Do I understand how to change one variable and control others?  Do I know the difference between an independent and dependent variable?

Key words: ice, melting point, freezing point, heat transfer, independent & dependent variables

Timeline: 3-4 periods

Period 1: Demos and literacy connection

1.  Pre-lab demonstration: Instant Freeze Water Sick Science! From Steve Spangler

https://www.youtube.com/watch?v=JEWQRJ49CPo

2.  Pre-lab demonstration #2 making a slushy using supercooled pop

https://www.thoughtco.com/instant-slushy-how-to-606424

3. Literacy Connection

Period 2: Skill Builders

  • Skill Builder (controlling variables, independent vs. dependent variables) – penny drop activity
  • Skill builder (observation vs. inference & conclusions) – Floating candles activity

 

Period 3:  Main Inquiry – Making ice cream

Period 4: Optional extension: M&M Solubility (full period inquiry)

 

 

Big Ideas:

Chemistry

  • Elements and compounds have specific properties that determine their uses.
  • The use of elements and compounds has both positive and negative effects on society and the environment.

 

Overall Expectations

A1.  demonstrate scientific investigation skills (related to both inquiry and research) in the four areas of skills (initiating and planning, performing and recording, analysing and interpreting, and communicating);

 

C1.  analyse how properties of common elements and/or simple compounds affect their use, and assess the social and environmental impact associated with their production or use; 

Specific Expectations:

Strand A – Scientific Investigative Skills

A1.1  formulate scientific questions about observed relationships, ideas, problems, and/or issues, make predictions, and/or formulate hypotheses to focus inquiries or research

A1.5  conduct inquiries, controlling some variables, adapting or extending procedures as required, and using standard equipment and materials safely, accurately, and effectively, to collect observations and data 

A1.6  gather data from laboratory and other sources, and organize and record the data using appropriate formats, including tables, flow charts, graphs, and/or diagrams

A1.8  analyse and interpret qualitative and/or quantitative data to determine whether the evidence supports or refutes the initial prediction or hypothesis, identifying possible sources of error, bias, or

A1.11  communicate ideas, plans, procedures, results, and conclusions orally, in writing, and/or in electronic presentations, using appropriate language and a variety of formats (e.g., data tables, laboratory reports, presentations, debates, simulations, models)

 

Chemistry Unit: Exploring Matter

C2.  investigate, through inquiry, physical and chemical properties of common elements and simple compounds;

C1.1  analyse how the chemical and physical properties of common elements and/or simple compounds affect the use of everyday materials that contain those elements and/or compounds [AI, C]  Sample issue: Chlorine compounds have strong disinfectant properties and are used in bleach and to purify water. However, these compounds can be highly toxic and must be used with care.   Sample questions: How do the compounds in road salt reduce ice accumulation?

C1.2  assess the social and environmental impact of the production or use of a common element or simple compound [AI, C] 

Sample issue: The use of road salt makes winter driving safer, reducing the social costs of motor vehicle accidents, including loss of human life. But the compounds in road salt damage roads and vehicles, pollute water systems, and harm animals and vegetation.

Key Concepts:

Physical properties: melting point, freezing point (ice cream inquiry) & solubility (M&M extension inquiry)

How to manipulate the independent variable and measure the affected dependent variable while controlling all the other variables.

Prior Skill Sets:

  • Understanding of variables (controlled, independent and dependent)
    • Can use skill builders to address this if needed

Prior Knowledge:

  • Knowledge of dependent and independent variables is an asset but not essential
  • Knowledge of the difference between an observation and a conclusion is important

Materials and Equipment:

Each pair of students would need:

  • 1 large Ziploc bag (gallon size)
  • 1 smaller Ziploc bag (sandwich size)
  • 2 spoons (to eat the ice cream)

Central station for the class:

  • Crushed ice, 1 standard sized bag will be used for 3-4 groups
  • 1/3 cup -1/2 cream (10%, also called half and half works well) per group*
  • salt (rock salt preferred but table salt will work too) (6-8 tbsp per group)
  • measuring spoons
  • measuring cups
  • 1 tbsp sugar per group
  • 1 tsp vanilla per group or other flavourings

*Non-dairy milk such as rice, coconut or almond milk could be used for students who are lactose intolerant or vegan

Watch this helpful 1 minute instructional video:

https://www.youtube.com/watch?v=Rxmhk9a7ZhI&feature=youtu.be

  • Having trouble accessing this video?  Copy and paste it directly into your browser.
  • Use the student resource document for the rest of the instructions.

Safety:

Since the students will be consuming the product, this inquiry should be done (optimally) in the Foods room or another non-laboratory space. 

Dietary restrictions:  for students with dietary restrictions, lactose free ice cream can be provided.  Another option is to provide a non-dairy alternative such as coconut milk instead of the cream.

Student Support Resources:

  • Penny drop skill builder
  • Floating candles skill builder
  • Ice cream inquiry – Smarter Science
  • Science of Ice Cream Literacy Connection
  • M&M Solubility inquiry

Related Background Resources and/or Links: shown throughout

Interesting website for more information:

1.  http://www.abc.net.au/science/surfingscientist/pdf/lesson_plan10.pdf

https://www.thirteen.org/edonline/ntti/resources/lessons/s_freeze/freeze3.pdf

2.  Has a good recipe and some good science connections:

https://www.thoughtco.com/how-to-make-ice-cream-in-a-bag-602195

3. Lactose free frozen dessert – gelato or sherbet

http://explorecuriocity.org/Explore/ArticleId/3017/ice-cream-science-3017.aspx

4.  About 9% of all milk produced in the US is for making ice cream

https://www.icecream.com/icecreaminfo

5.  A video by the Chem Society

https://www.acs.org/content/dam/acsorg/education/resources/highschool/chemmatters/archive/chemmatters-feb2014-ice-cream.pdf

Assessment Opportunities:

  • Skill builders: penny drop & floating candles (Assessment as Learning)
  • Ice Cream Inquiry: Assessment as Learning and Assessment of Learning
  • Science of Ice Cream Literacy Connection (Assessment of Learning)
  • M&M Solubility (Assessment of and as Learning)

Future Opportunities / Extensions:

Other ideas for activities/demonstrations for which you can emphasize observations vs. inferences:

1.  How to burn a candle underwater

https://www.neatorama.com/2015/10/01/How-to-Burn-a-Candle-Underwater/

2.  Dancing raisins

 https://www.stevespanglerscience.com/lab/experiments/dancing-raisins-the-bubble-lifter/

4.  Sink or Swim – it is about another physical property (density)

https://www.youtube.com/watch?v=I_ocVSX7ZCI

Extension: natural vs. chemical methods of de-icing such as using cabbage juice, etc. Good for a science fair project

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